GMAT Quiz: Analyze Arguments

What this quiz covers

This quiz focuses on Analyze Arguments, giving you a quick way to practice the rules, question types, and explanations that matter most for GMAT.

How to use this quiz

Try each quiz question before looking at the correct answer. Use the explanations to review missed ideas, then come back to similar questions until the pattern feels familiar.

Question 1

1. Surveys show that most of the chain's customers are unaware of the chain's social-media accounts.
2. A significant portion of this chain's social-media advertising budget is allocated to maintaining rather than expanding its online presence.
3. In some years during the decade, the chain's revenue from in-store purchases declined even though total revenue increased.
4. Several rival coffee chains that did not increase social-media advertising over the last decade also experienced steady revenue growth during that period. (correct answer)

Explanation: When you encounter a "weaken the argument" question, you need to identify the logical flaw in the reasoning and find evidence that undermines the conclusion. Here, the analyst commits a classic causation error: assuming that because two events occurred together (increased social media spending and revenue growth), one caused the other. The correct answer is D because it directly challenges the causal claim. If rival coffee chains achieved similar revenue growth without increasing social media advertising, this suggests that other factors—not the advertising—likely drove the revenue increases. This alternative explanation severely weakens the analyst's conclusion that the advertising caused the growth. Let's examine why the other options don't weaken the argument as effectively: A) suggests the advertising might not be reaching customers, but this doesn't directly challenge whether it caused revenue growth—the advertising could still be effective through indirect means. B) discusses how the budget is allocated but doesn't address whether the spending actually caused revenue increases. C) shifts focus to a different revenue breakdown (in-store vs. total) without challenging the core causal relationship between advertising and overall revenue. Remember that strengthening and weakening questions often hinge on causation vs. correlation. When an argument claims that X caused Y based solely on their co-occurrence, look for answer choices that provide alternative explanations for Y or show that Y happens without X. These "other causes" or "effect without cause" scenarios are powerful tools for undermining causal arguments on the GMAT.

Question 2

1. Businesses in other cities that reduced parking availability reported decreased customer visits by car.
2. Public transit routes that serve downtown are already operating at full capacity during peak hours.
3. Rents in neighborhoods within five kilometers of downtown have been rising faster than wages for several years. (correct answer)
4. Many suburban commuters currently drive only because safe bicycle lanes are lacking along part of their route.

Explanation: This is a strengthen question testing your ability to identify which piece of evidence best supports the urban planner's conclusion that eliminating parking spaces won't reduce congestion. The planner's argument follows this logic: Since only 8% of employees live within biking distance and most won't move, removing parking won't get people to cycle instead of drive. For this reasoning to be strongest, you need evidence that reinforces why people won't switch from driving to cycling. Choice C is correct because rising rents within biking distance directly supports the planner's claim. If housing costs near downtown are outpacing wages, this creates a financial barrier that makes it even less likely that the 92% of employees living farther away will move closer. This strengthens the argument by showing there's an economic reason why the current residential pattern will persist. Choice A is wrong because decreased customer visits doesn't address whether employee commuting patterns will change. Choice B actually weakens the planner's argument—if public transit is maxed out, cycling becomes a more attractive alternative for some commuters, potentially reducing car traffic. Choice D directly contradicts the planner's reasoning by suggesting that many suburban commuters would cycle if safe lanes existed, implying the proposal might actually work. Strategy tip: In strengthen questions, look for evidence that reinforces the argument's key assumptions. Here, the assumption was that residential patterns won't change. The correct answer provided economic reasoning for why that assumption holds true.

Question 3

1. Objectives for many agencies are revised upward whenever additional funds are granted.
2. A majority of agency budgets consists of fixed costs that cannot be easily reduced even after leadership changes.
3. Agencies that replaced top leadership without receiving extra funds have rarely improved their performance metrics. (correct answer)
4. Public opinion data indicate that voters favor replacing leadership over allocating more funds to failing agencies.

Explanation: Critical reasoning questions that ask what "most undermines" an argument are testing your ability to identify information that weakens the author's conclusion. You need to find the choice that makes the recommended course of action seem less effective or advisable. The columnist argues that governments should replace agency leadership instead of providing additional funding when agencies fail to meet objectives. This recommendation rests on the premise that leadership changes will be more effective than budget increases at improving performance. Choice C directly attacks this assumption by showing that replacing leadership without additional funds "rarely" leads to improved performance metrics. If leadership changes don't typically work, then the columnist's recommended solution is fundamentally flawed. This evidence suggests the proposed alternative would be just as ineffective as increased funding. Choice A is irrelevant because it discusses what happens when funds are granted, but doesn't address whether leadership replacement would be better. Choice B mentions fixed costs remaining after leadership changes, but this doesn't necessarily mean the changes won't improve performance—it's just describing budget constraints. Choice D actually supports the columnist's position by showing public preference aligns with the recommendation, making it a strengthener rather than a weakener. When tackling "undermine" questions, look for answer choices that directly challenge the effectiveness or wisdom of the proposed solution. The strongest undermining evidence shows that the recommended approach has a poor track record of success.

Question 4

1. Radiocarbon dating indicates that the early settlement layers span a period of nearly three centuries.
2. The later layers contain bones of large mammals introduced by the settlers and known to prey on ground-nesting birds. (correct answer)
3. Traditions among the island's present-day inhabitants include stories describing the rails as sacred birds never to be harmed.
4. Detailed analysis shows that rail bones in the earliest layers bear cut marks consistent with butchering practices.

Explanation: This is a classic "weaken the argument" question in critical reasoning. When you encounter these, your job is to find evidence that makes the author's conclusion less likely to be true, not necessarily prove it wrong entirely. The zoologist concludes that early settlers hunted the rails to extinction based on a simple pattern: rail bones appear in early settlement layers but disappear from later layers. To weaken this conclusion, you need an alternative explanation for why the rails disappeared. Choice B provides exactly that alternative. If large mammals introduced by settlers preyed on ground-nesting rails, this could explain the birds' extinction without requiring direct hunting by humans. Since rails are flightless and nest on the ground, they would be particularly vulnerable to introduced predators like cats, dogs, or pigs. This creates reasonable doubt about the hunting hypothesis. Let's examine why the other choices don't work. Choice A actually strengthens the argument—if early settlers had three centuries to hunt the rails, that provides ample time for extinction through hunting. Choice C might seem relevant, but present-day traditions don't necessarily reflect the beliefs or practices of the original settlers centuries ago. Choice D directly supports the zoologist's conclusion by providing physical evidence of butchering. Strategy tip: In GMAT critical reasoning, "weaken" questions often hinge on alternative causation. When an argument claims "X caused Y," look for answer choices that suggest "Z could have caused Y instead." The correct answer doesn't need to prove the original cause wrong—just make it less certain.

Question 5

1. Peer institutions that reduced shelving later expanded it again after receiving alumni complaints.
2. The proposed retail spaces would be managed by third-party vendors that must share profits with the university.
3. Surveys reveal that while students increasingly access articles online, they still rely on printed monographs for advanced research projects. (correct answer)
4. Many of the library's older printed volumes are duplicated in publicly available online archives.

Explanation: When you encounter a "challenge the prediction" question on the GMAT, you're looking for evidence that directly undermines the conclusion's key assumption. Here, the official predicts that reducing library space "will not harm academic outcomes" because "students now prefer digital materials." The correct answer is C because it reveals a critical gap in the official's reasoning. While students may indeed prefer digital access for some materials (like articles), they still depend on printed books specifically for advanced research. This directly contradicts the assumption that digital preference is universal and complete, showing that removing physical books could indeed harm academic outcomes for students doing sophisticated research work. Let's examine why the other options fail to challenge the prediction effectively: A) Alumni complaints don't directly address whether academic outcomes will suffer—complaints could stem from nostalgia or other non-academic concerns. B) The profit-sharing arrangement with vendors relates to the financial viability of the retail plan, not to whether academic outcomes will be harmed by reduced book access. D) This actually supports the official's position by suggesting that many physical books have digital equivalents available, making the space reduction less problematic. Strategy tip: In "challenge the conclusion" questions, ignore answers that address tangential issues like finances or public relations. Focus on finding evidence that directly attacks the logical link between the premise and conclusion. The strongest challenges reveal overlooked exceptions or contradictory evidence about the specific claim being made.

Question 6

1. Cooks who add salt to boiling water do so solely to shorten cooking time rather than to improve flavor.
2. No chemical interaction other than boiling-point elevation caused by salt can affect the rate at which pasta cooks. (correct answer)
3. Cooking time for pasta decreases only if the temperature of the cooking water increases by more than 0.5°C.
4. The texture of pasta is unaffected by salt concentrations low enough to raise boiling point by less than 0.5°C.

Explanation: Critical reasoning questions asking "which assumption does the argument rely on" test your ability to identify unstated premises that must be true for the argument's logic to work. The chef's argument follows this logic: Salt raises boiling point by less than 0.5°C → This small increase won't alter cooking time → Therefore, salt can't make pasta cook faster. The chef assumes that boiling point elevation is the only way salt could affect cooking speed. If salt influenced pasta cooking through some other chemical mechanism (like changing how starch molecules behave or altering protein structures), then the argument would fall apart even if boiling point barely changes. Choice B captures this assumption perfectly: the chef must assume no other chemical interaction besides boiling-point elevation can affect cooking rate. Choice A is wrong because the chef's scientific argument doesn't depend on cooks' motivations—whether they add salt for speed or flavor is irrelevant to whether salt actually affects cooking time. Choice C misstates the relationship by claiming cooking time decreases only if temperature rises more than 0.5°C, but the chef's point is that such a small increase is insufficient, not that larger increases are the sole way to reduce cooking time. Choice D focuses on texture rather than cooking speed, which isn't what the chef's argument addresses. Strategy tip: When identifying assumptions in GMAT arguments, look for gaps between evidence and conclusion. Ask yourself: "What must the author believe is true that they haven't explicitly stated?" The correct assumption will be something that, if false, would seriously damage the argument's logic.

Question 7

1. For many painters, works executed later in life command higher prices regardless of subject matter.
2. Several art historians rank Painter Z's technical skill in her early period as equal to that in her later period.
3. When early works by Painter Z depict the same fashionable themes as the later works, they sell for prices comparable to those of the later works. (correct answer)
4. The materials used in Painter Z's early works are less expensive than those used in her later works.

Explanation: When you encounter a "strengthen the argument" question, you need to identify the conclusion and find evidence that makes it more likely to be true. The critic concludes that price differences are driven by subject matter, not technique, based on the observation that later works with fashionable themes command higher prices. Choice C provides the perfect test case: if early works depicting the same fashionable themes sell for comparable prices to later works, this directly supports the critic's theory. It isolates subject matter as the key variable while controlling for the time period, essentially proving that theme drives price regardless of when the work was created. Choice A actually weakens the argument by suggesting that timing itself (regardless of subject matter) affects prices for many painters. This contradicts the critic's subject-matter theory. Choice B only addresses one part of the competing explanation about technique, but doesn't definitively prove technique isn't a factor—art historians could still disagree about overall artistic merit. Choice D introduces an irrelevant factor (material costs) that doesn't help distinguish between the technique and subject matter explanations. The key strategy for strengthen questions is to look for answer choices that provide additional evidence supporting the conclusion or that eliminate alternative explanations. Choice C does both: it confirms the subject matter theory while ruling out the possibility that time period or technique development accounts for the price difference.

Question 8

1. The dam was engineered to release water at volumes that should prevent downstream sediment starvation.
2. Sediment trapped by dams can accumulate and compromise the dam's structural integrity.
3. Logging activity often increases soil runoff into rivers, thereby speeding riverbank erosion. (correct answer)
4. Some stretches of the river upstream from the dam also exhibit signs of erosion.

Explanation: This question tests your ability to identify what completes a logical argument by providing the missing link between evidence and conclusion. The engineer argues that logging, not the dam, causes the increased erosion. The evidence presented is that logging activity intensified after dam construction. However, there's a logical gap: the engineer hasn't explained how logging would cause riverbank erosion. To complete this argument, you need the missing piece that connects logging activity to erosion. Choice C provides exactly this connection by explaining that "logging activity often increases soil runoff into rivers, thereby speeding riverbank erosion." This directly links the engineer's evidence (increased logging) to the conclusion (logging causes erosion) by explaining the mechanism. Choice A is incorrect because it supports the dam's design but doesn't explain how logging causes erosion. The engineer needs to prove logging is the culprit, not defend the dam's engineering. Choice B is wrong because it discusses dam maintenance issues, which is irrelevant to proving that logging causes downstream erosion. Choice D fails because upstream erosion doesn't help prove that downstream logging causes downstream erosion. If anything, widespread erosion might suggest the dam is the common factor. When you encounter "complete the argument" questions, look for the missing logical link. The correct answer will bridge the gap between the evidence presented and the conclusion drawn. Don't get distracted by choices that introduce new topics or support opposing viewpoints.

Question 9

1. Snacking between meals is the primary source of excess calorie intake for most individuals.
2. High-protein breakfasts are generally lower in calories than high-carbohydrate breakfasts.
3. Participants who felt less hungry before lunch consumed fewer total calories over the course of the day.
4. Feelings of hunger correlate with the likelihood of actually consuming snacks before lunch. (correct answer)

Explanation: When you encounter assumption questions on the GMAT, you're looking for an unstated premise that must be true for the argument to work. The nutritionist's logic flows from "feeling less hungry" to recommending high-protein breakfasts to "reduce snacking," but there's a gap between hunger feelings and actual snacking behavior. Answer choice D correctly identifies this gap. The nutritionist assumes that when people feel less hungry, they're also less likely to actually snack. Without this connection, the recommendation falls apart—people could feel less hungry but still snack just as much due to habit, boredom, or other factors. This assumption is essential for the conclusion to follow logically from the evidence. Let's examine why the other choices don't work. Choice A discusses snacking being the "primary source" of excess calories, but the nutritionist's recommendation doesn't require snacking to be the main problem—just that reducing it would be beneficial. Choice B compares calorie content of different breakfast types, but the argument focuses on hunger feelings and snacking behavior, not total breakfast calories. Choice C extends to total daily calorie consumption, but the nutritionist's specific recommendation targets snacking behavior, not overall caloric intake. The key strategy for assumption questions is to identify the logical gap between evidence and conclusion. Look for what the author takes for granted but never explicitly states. Often, as here, it's a connection between two different concepts—in this case, the link between subjective feelings (hunger) and objective behavior (snacking).

Question 10

1. The cost of administering elections in Region Q decreased after online registration was introduced.
2. Most voters in Region Q had access to the internet well before online registration was implemented.
3. Regions that have long offered online registration show no consistent pattern of higher turnout than regions that do not.
4. During the same period, several highly contested local ballot initiatives energized voters in Region Q. (correct answer)

Explanation: When you see a question asking what "undermines" an inference, you're dealing with a classic causal reasoning problem. The political scientist concludes that online registration caused increased voter turnout because it was the only major change that occurred. To weaken this argument, you need to find an alternative explanation for the increased turnout. The correct answer is D because it provides a compelling alternative cause for the voter turnout increase. If several highly contested local ballot initiatives energized voters during the same period, this could fully explain the rise in turnout without any contribution from online registration. This directly challenges the scientist's causal inference by offering a different, plausible explanation for the same effect. Let's examine why the other choices fail to undermine the argument. Choice A about decreased administrative costs is irrelevant to voter turnout levels—it doesn't suggest an alternative cause or challenge the causal relationship. Choice B states that voters already had internet access, but this actually supports the argument by showing that the technical barrier to using online registration was already removed, making it more likely that the new system would increase participation. Choice C discusses long-term patterns in other regions, but this doesn't address what specifically happened in Region Q during the time period in question—the scientist's argument is about this particular instance, not general patterns. For GMAT causal reasoning questions, always look for answer choices that provide alternative explanations for the observed effect. The strongest undermining evidence typically introduces a different potential cause that occurred during the same timeframe.

Question 11

1. Changes in land use, such as deforestation, can influence local weather patterns even without population growth.
2. Thunderstorm frequency can vary naturally over multi-decade cycles unrelated to climate change.
3. Data collection methods for severe weather were improved five years ago, resulting in more complete reporting. (correct answer)
4. Neighboring counties with similar climates have not experienced an increase in severe thunderstorms.

Explanation: When you encounter GMAT critical reasoning questions asking about flaws in reasoning, look for gaps between the evidence presented and the conclusion drawn. The key is identifying what alternative explanations the argument fails to consider. The meteorologist concludes that climate change caused the increase in severe thunderstorms, ruling out urban expansion because population remained constant. However, this reasoning assumes that the observed increase in reported storms actually reflects a real increase in storm frequency. Option C reveals this critical flaw: if data collection methods improved five years ago, the apparent doubling could simply result from better detection and reporting of storms that were always occurring but previously went unrecorded. Option A is incorrect because while land use changes could affect weather patterns, the meteorologist already addresses this by noting constant population (though this response isn't perfect, it doesn't expose the fundamental measurement flaw). Option B suggests natural cycles could explain the increase, but this doesn't identify a flaw in the meteorologist's logic—it just offers an alternative explanation within the same framework. Option D about neighboring counties is irrelevant because local weather patterns can vary significantly even between adjacent areas with similar climates. The most devastating flaw is when an argument mistakes changes in measurement for changes in the phenomenon being measured. Always ask yourself: "Could improved detection, reporting, or measurement methods explain the observed change?" This is a common trap in arguments about statistical trends, especially in scientific contexts where measurement capabilities evolve over time.

Question 12

1. Firm S's management is willing to allocate resources necessary for an effective mindfulness program.
2. Participants in Firm R's mindfulness program did not differ significantly from nonparticipants at Firm S in job duties.
3. Workplace stress levels at Firm R and Firm S were similar before Firm R implemented its mindfulness program. (correct answer)
4. Mindfulness programs at other firms have been shown to reduce employee stress by more than 10 percent.

Explanation: When analyzing assumption questions in critical reasoning, you need to identify what unstated premise the argument requires to be valid. The analyst concludes that implementing a mindfulness program at Firm S would reduce stress by about 10 percent based on results from Firm R. The correct answer is C because this assumption is essential for the comparison to be meaningful. If Firm R started with much higher or lower stress levels than Firm S currently has, then the 10 percent reduction observed at Firm R wouldn't predict the same percentage reduction at Firm S. For the analyst's conclusion to hold, both firms must have had comparable baseline stress levels before Firm R implemented its program. Let's examine why the other options aren't necessary assumptions: A addresses implementation feasibility, but the analyst's conclusion assumes implementation will happen—this doesn't affect whether the program would work if implemented. B focuses on comparing participants to nonparticipants, but the argument compares Firm R participants to all Firm S employees, making job duty similarities irrelevant to the logic. D suggests other programs achieved greater reductions, but this neither supports nor undermines the prediction of a 10 percent reduction at Firm S. To tackle assumption questions effectively, use the negation test: if negating a statement destroys the argument, it's a necessary assumption. Negating C (the firms had very different baseline stress levels) would make the 10 percent prediction unreliable, while negating the other choices wouldn't fundamentally undermine the analyst's reasoning.

Question 13

1. Fuel costs constitute a smaller share of bus operating expenses than driver wages and vehicle maintenance.
2. Bus passengers rate reliability of service as their top priority, ahead of speed and comfort. (correct answer)
3. Many passengers who ride during peak hours also occasionally ride during off-peak hours.
4. Other cities that reduced off-peak bus service experienced public protests from affected residents.

Explanation: Critical reasoning questions that ask you to weaken an argument require you to find evidence that undermines the conclusion or reveals a flaw in the reasoning. The government report concludes that reducing off-peak bus frequency would save money without significantly affecting passengers because buses are mostly empty during those times. The correct answer is B because it reveals a critical flaw in the proposal's logic. If passengers prioritize reliability above all else, then reducing service frequency directly attacks what matters most to them. Even if buses are only 25% full, those passengers depend on consistent, reliable service. Making buses less frequent makes the service less reliable, significantly affecting the passengers who do use off-peak service—contradicting the report's claim that passengers wouldn't be significantly affected. Looking at the wrong answers: A doesn't weaken the argument because regardless of which costs are higher, reducing service frequency would still save money by cutting operational expenses across all categories. C actually supports the proposal since passengers who mainly ride during peak hours would be largely unaffected by off-peak reductions. D mentions protests but doesn't explain whether those protests were justified or whether the service cuts actually harmed passengers—it's too vague to meaningfully weaken the argument. When tackling "weaken" questions, focus on finding answer choices that either attack the reasoning between premises and conclusion or introduce new information that makes the conclusion less likely to be true. The correct answer should create genuine doubt about the argument's validity.

Question 14

1. The drop in smoking was greater among older adults than among adolescents.
2. During the same period, Country M also increased taxes on cigarettes by 25 percent. (correct answer)
3. Neighboring countries that did not change cigarette packaging experienced a similar decline in smoking rates.
4. Some smokers in Country M began purchasing branded cigarettes illegally imported from abroad.

Explanation: When you encounter a "challenge the reasoning" question, you're looking for evidence that weakens the causal relationship the author has drawn. The health economist concludes that plain packaging caused the smoking decline, but this assumes plain packaging was the primary factor at work. The correct answer is B because it introduces a major alternative explanation. If cigarette taxes increased by 25% during the same period, this significant price hike could easily account for the 6% drop in smoking rates. Economic research consistently shows that higher tobacco taxes are one of the most effective ways to reduce smoking. This alternative cause seriously undermines the economist's attribution of the decline to plain packaging alone. Let's examine why the other options don't challenge the reasoning as effectively: A) The demographic breakdown of who quit smoking doesn't challenge whether plain packaging caused the overall decline—it just describes the pattern of the decline. C) This actually supports the economist's reasoning by suggesting plain packaging made a difference, since countries without it saw similar declines for other reasons. D) Some illegal purchasing doesn't negate the overall effectiveness claim. Even if a small portion of smokers found workarounds, the national rate still dropped significantly. Remember that GMAT critical reasoning questions often test your ability to identify when correlation might not equal causation. When evaluating causal arguments, always look for alternative explanations that could account for the observed effect—especially major policy changes or economic factors that occurred simultaneously.

Question 15

1. The snail's population growth rate slows dramatically in cooler months.
2. The bird also eats the fruits of several other rare plant species endemic to the two islands. (correct answer)
3. The bird has successfully controlled the snail on nearby islands that lack orchid species P.
4. Captive breeding programs for orchid species P have so far been unable to produce viable seedlings.

Explanation: When you encounter a question asking what "undermines" a plan, you're looking for information that reveals a serious flaw or unintended consequence that would make the plan counterproductive or ineffective. The botanist's plan is straightforward: introduce a bird to control the snail population and save the rare orchid. For this plan to work, the bird needs to solve the orchid problem without creating worse problems. Choice B reveals a critical flaw—the bird doesn't just eat snails; it also eats fruits of other rare endemic plants. This means the "solution" would potentially harm multiple rare species to save one, creating a conservation disaster rather than a success. Choice A is wrong because seasonal population changes don't undermine the overall plan—the bird could still provide year-round control when needed most. Choice C actually supports the plan by showing the bird has successfully controlled snails elsewhere, demonstrating its effectiveness. Choice D about captive breeding failures is irrelevant to whether introducing the bird is a good solution; the focus is on protecting wild seedlings from snail predation. The key insight is that D introduces an entirely separate issue (captive breeding) that doesn't relate to the field conservation strategy being proposed. Meanwhile, B directly shows how the proposed solution creates new problems. Strategy tip: On GMAT Critical Reasoning questions about undermining plans, look for unintended consequences or hidden costs that make the cure worse than the disease. The most effective undermining answers reveal flaws within the plan's own logic.

Question 16

1. The number of licensed taxi drivers in City Z increased dramatically following the entry of ride-sharing services.
2. Ride-sharing fares in City Z are typically lower than taxi fares for comparable trips. (correct answer)
3. Many ride-sharing drivers in City Z previously worked as taxi drivers but switched occupations.
4. City Z's public transit system expanded service frequency during the period in question.

Explanation: This question tests your ability to strengthen a causal argument by identifying evidence that supports the proposed cause-effect relationship. The economist argues that ride-sharing services caused taxi drivers' income decline by capturing their customers. To strengthen this argument, you need evidence that directly supports the connection between ride-sharing services and lost taxi business. Choice B provides exactly this: if ride-sharing fares are typically lower than taxi fares, this gives customers a clear economic incentive to switch from taxis to ride-sharing services. Lower prices are a powerful driver of consumer behavior, making it highly plausible that ride-sharing captured taxi customers. Choice A actually weakens the argument. If the number of taxi drivers increased dramatically, the 20% income decline could simply result from more drivers splitting the same amount of business, rather than ride-sharing stealing customers. Choice C is tempting but irrelevant to the conclusion. While it shows ride-sharing affected the taxi industry, drivers switching occupations doesn't prove that ride-sharing captured taxi customers—the customer base could have remained unchanged. Choice D weakens the argument by suggesting an alternative explanation. If public transit expanded during this period, the income decline might result from customers switching to public transit rather than ride-sharing. Strategy tip: In strengthen questions, look for answer choices that make the proposed cause-effect relationship more likely to be true. The best strengtheners often provide a logical mechanism or remove alternative explanations that could account for the observed effect.

Question 17

1. Funds allocated for building parks cannot legally be used for road expansion.
2. Some city council members who oppose road expansion nevertheless oppose building new parks for budgetary reasons.
3. The survey was conducted before the most recent property-tax increase was announced.
4. Voter turnout is typically higher among residents concerned with traffic congestion than among residents concerned with green space. (correct answer)

Explanation: When you encounter a "weaken the argument" question, you need to identify the gap between the evidence and conclusion, then find an answer choice that exploits that gap. The editorial's logic flows like this: Survey shows 60% favor parks over 30% for roads → Council members supporting parks will likely win re-election. The key assumption here is that survey preferences translate directly into voting behavior and election outcomes. Choice D destroys this assumption by revealing that the people who care about roads (and would vote against park supporters) are more likely to actually vote than people who care about parks. Even though park supporters outnumber road supporters 2-to-1 in the survey, if road supporters have significantly higher voter turnout, they could easily outnumber park supporters at the ballot box. This directly undermines the conclusion that pro-park council members will win. Choice A doesn't weaken the argument—legal restrictions on fund transfers don't change voter preferences or election outcomes. Choice B actually supports the editorial by suggesting some anti-road council members might lose votes from budget hawks, making pro-park stances even more appealing. Choice C mentions timing but doesn't establish that property tax increases would change the park vs. road preference dynamic. Remember: In "weaken" questions, look for answer choices that attack the connection between evidence and conclusion. The most effective weakeners often reveal that the evidence doesn't actually support the conclusion because of some overlooked factor—here, the difference between survey responses and actual voting behavior.

Question 18

1. Company Q's product prices are comparable to those of its faster-loading competitors.
2. A significant portion of visitors leave Company Q's website before it finishes loading. (correct answer)
3. Reducing the website's load time to three seconds would require only minor modifications.
4. Visitors who stay on Company Q's site for more than one minute are highly likely to make a purchase.

Explanation: When you encounter strengthen questions on the GMAT, look for answer choices that provide additional evidence supporting the argument's logical connection. Here, the consultant argues that reducing load time will increase sales because faster sites retain more visitors. Answer choice B strengthens this argument by confirming that Company Q actually loses visitors due to slow loading—a crucial missing link. If visitors are indeed leaving before the site loads, then the premise about visitor retention directly applies to Q's situation, making the conclusion about increased sales more credible. Let's examine why the other choices don't strengthen the argument as effectively. Choice A about comparable pricing is irrelevant to the load time argument—price competition doesn't affect whether faster loading leads to more sales. Choice C about minor modifications being needed addresses implementation difficulty, not whether the strategy will work. Choice D about visitors staying longer being likely to purchase actually works against the argument by suggesting that Q's current visitors (who tolerate the slow loading) are already highly likely to buy. The key trap here is confusing "helpful information" with "strengthening evidence." While C and D provide potentially useful context, they don't directly support the causal relationship the consultant claims between load time and sales. Remember: strengthen questions require you to find evidence that makes the conclusion more likely to be true, not just information that's generally relevant to the topic. Focus on bridging logical gaps in the argument's reasoning.

Question 19

1. Several modern camping equipment fragments were found in the same layer as the marked bones.
2. Some prehistoric cultures possessed copper tools, which can leave marks resembling those made by modern metal blades.
3. Chemical analysis shows that soil around the marked bones contains residues from contemporary cleaning agents. (correct answer)
4. Bones bearing no tool marks at all were also found at Site K.

Explanation: When you encounter strengthen questions on the GMAT, you need to identify evidence that makes the conclusion more likely to be true. The anthropologist concludes that bones showing metal tool marks were altered by recent visitors, making prehistoric hunting conclusions unreliable. Choice C provides the strongest support because contemporary cleaning agents in the soil directly indicate recent human activity at the exact location of the questioned bones. This chemical evidence creates a clear temporal link between modern interference and the suspicious tool marks, making the anthropologist's theory about recent alteration much more credible. Choice A is tempting because modern camping equipment suggests recent visitors, but these fragments could be from a different time period or location within the site. The connection to the specific marked bones isn't direct enough. Choice B actually weakens the argument by offering an alternative explanation—if prehistoric copper tools could create similar marks, then the bones might genuinely be prehistoric rather than recently altered. Choice D is irrelevant to the core issue. Finding unmarked bones tells us nothing about whether the marked bones were altered recently or prehistorically. The key strategy for strengthen questions is to look for evidence that eliminates alternative explanations or provides direct support for the conclusion. Choice C does both—it eliminates the possibility that the marks are truly prehistoric while providing concrete evidence of recent human interference. Always choose the answer that creates the most direct causal or temporal connection to the conclusion.

Question 20

1. Demand for metal M from the electronics industry has increased steadily over the past decade.
2. Unlike in previous inflationary periods, central banks now hold large reserves of metal M and plan to sell portions of those reserves. (correct answer)
3. Some analysts predict that inflation will stabilize sooner than the advisor expects.
4. The transaction costs associated with purchasing and storing metal M have recently declined.

Explanation: When you encounter argument weakening questions, look for answer choices that introduce new information that undermines a key assumption in the original reasoning. The financial advisor's argument relies on the assumption that historical patterns will continue unchanged. The advisor argues that because metal M's value has historically risen during inflation, and inflation is expected to rise, investors should buy metal M now. This reasoning assumes that the same conditions that existed during previous inflationary periods will exist next year. Choice B directly challenges this assumption by introducing a significant new factor: central banks now hold large reserves of metal M and plan to sell portions during the expected inflationary period. This is crucial because when large institutional holders flood the market with supply, it can suppress prices regardless of demand from inflation. The historical pattern the advisor relies on likely didn't account for this massive potential supply increase. Choice A actually strengthens the argument by suggesting additional demand for metal M. Choice C weakens the premise about inflation timing but doesn't challenge the core relationship between inflation and metal M's value. Choice D strengthens the investment case by making metal M purchases more cost-effective. The key trap here is confusing premise attacks with assumption attacks. While C attacks the inflation premise, B attacks the deeper assumption that past conditions will repeat. In GMAT Critical Reasoning, the strongest weakening answers often introduce new factors that break the assumed causal relationship, rather than simply questioning the premises. Always ask: "What is this argument taking for granted?"