"Tepid" means moderately warm. The best choice is "lukewarm" because it also means moderately warm. Considering the other choices, "scold" means find fault with angrily and verbally, "clever" means intelligent or witty, and "deep" means extending far beneath the surface.

"Edible" means able to be eaten. Notice the suffix "-ible," which suggests that a word means able to be something. Watch for suffix and prefix patterns in English, as they can help you figure out the meanings of words you have not seen before.

"Dry" is defined as without moisture or liquid. Since "arid" climates are characterized as dry and having little rain, "arid" is the best answer choice. "Moist" is an antonym of "dry."

Something that is "rigid" is stiff or firm, so "firm" is the correct answer. None of the other answer choices are close in meaning to "rigid": "adaptable" means able to adjust oneself to fit a given situation; "sufficient" means enough; "elastic" means flexible; and "loose" means not tightly secured or baggy in fit.

"Hollow" means empty.

The adjective "pliable" describes the quality of being easy to bend; a pliable material, therefore, is not stiff or "unyielding." Instead, it is "flexible," which is our correct synonym. The two remaining answer choices, though also adjectives in at least some cases, are unrelated to this term. "Askew" refers to the quality of being crooked, as in a poster that is hung at a slant on the wall. "Routine," our final choice, can describe an activity that is unremarkable or part of a regular schedule. Note that "routine" can also be used as a noun, as in our "daily routine." Finally, "honest" means truthful.

A material like steel is inflexible and would be considered rigid.  Thus, the best way to characterize something rigid is to term it as stiff.

Something that is "firm" holds its form easily and is difficult to bend out of shape. The word that best reflects this characteristic as a synonym is therefore "stiff," which means inflexible. The other answer choices are unrelated to the word "firm."

Something that is "frail" is easily broken. Something that is "weak" is lacking strength, and therefore also breaks very easily. Given the similarities between these two words, "weak" is the best synonym for "frail."

A person who appears "unkempt" looks messy, as if he or she has not groomed themselves, and generally lacking in personal maintenance. Have you ever left for school in a hurry, perhaps with unbrushed hair or wrinkled clothes? You likely seemed unkempt. Now that we know the meaning of the given term, let's examine the choices. "Tidy" means neat and organized, so it cannot be our answer. "Forceful," which means powerful, and "mistaken," which means incorrect, are not related to an untidy appearance. We are left with "disheveled," which means physically messy or out of order. We have found our synonym!