The word "fatuous" is an adjective that means foolish or lacking wit. "Dull," which can mean lacking wit, shares the same definition and is therefore the best answer choice. Considering the other choices, "bright" in this context is an antonym of "fatuous" since it can mean intelligent. "Portly" means heavy or fat.

A person who is "glib" is smooth-talking, meaning they are able to speak well. The best choice is thus "smooth-talking," since it is part of the definition of "glib." Considering the other choices, "crass" means rude or gross, "dumbfounded" means astonished, "pivotal" means crucial or important, and "portable" means able to be transported easily.

"Combative" is an adjective that means ready to fight. The best choice is "quarrelsome," since it holds a similar meaning of ready to argue. Considering the other choices, "obedient" is an antonym which means complying with authority, "masterful" means skillful, "torrid" means very hot and arid, or passionate when describing a romantic relationship.

“Diligent” means careful, hard-working, and taking care to do something well, so "careful" is the best synonym amongst the answer choices. “Approachable” means friendly and thus easily approached; “demonstrative” means demonstrating something or openly showing feelings or affection; “eloquent” means well-spoken; and “elegant” means having grace, sophistication, and good taste.

“Capricious” means changing in response to the slightest whims, so "changeable" is the correct answer. Being “reliable” is the opposite of being “capricious”; “flexible” means bendable; “humane” means compassionate or treating something like a human should be treated; and "wanton” means random.

“Dissolute” means of poor moral character, depraved and debauched. “Depraved” means lacking moral character or doing sinful or immoral things, so it is the correct answer. “Imperious” means arrogant and controlling; “laudable” means deserving of praise; “meddlesome” means interfering or prone to getting involved in situations in which one is not supposed to; “vulnerable” means able to be hurt or damaged.

“Contemptuous” means showing scorn and hatred for something, so "scornful" is the correct answer. As for the other answer choices, “remorseful” means full of guilt and sadness over something one did wrong; “docile” means calm and compliant; “impregnable” means unable to be captured or broken; and “surreptitious” means secret and sneaky.

“Gregarious” means friendly and sociable, so "sociable" is the correct answer. As for the other answer choices, “implacable” means unappeasable, unable to be placated, or not forgiving; “domineering” means controlling; “complementary” means something that works well with something else; and “supplementary” means additional.

Someone who is “stoic” is unemotional and unresponsive when faced with painful or difficult situations, so "unemotional" is the best answer. As for the other answer choices, “responsive” means reacting or done in response; “critical,” when referring to the significance of something, means highly important, though it can also mean pointing out the faults in something; “fortuitous” means owed to good-fortune or lucky; and “frivolous” means purposeless and not serious.

“Garrulous” means talkative, so "talkative" is the correct answer. As for the other answer choices, “austere” means severe or severe-looking; “ironic” describes a situation in which what you get is not what you expected, often in a funny or wry way; “jovial” means friendly; and “condemning” means heavily criticizing.