“Sparse” is an adjective that can mean scattered, while “dense” is an adjective that can mean compact or crowded together. So, “sparse” and “dense” are antonyms, and we need to pick out an answer choice that is an antonym of “limited,” an adjective that means restricted. So, that means that “finite” cannot be the correct answer, because “finite” is an adjective that can mean having limits, making it a synonym, not an antonym, of “limited.” “Endless,” however, is an adjective that can mean having no end or seeming to have no end. Because “limited” is an antonym of “endless” just like “sparse” is an antonym of “dense,” “endless” is the correct answer.

“Rise” and “fall” are antonyms, so we need to pick out an answer choice which means the opposite of “facilitate,” a verb that means make a process easier. That means that “encourage” cannot be the correct answer, because "encourage" means help, support, or inspire, making it a synonym, not an antonym, of “facilitate.” “Hinder,” however, is a verb that means create delays in some process, and because “hinder” is an antonym of “facilitate” just as “rise” is an antonym of “fall,” “hinder” is the correct answer.

“Incriminate” is a verb that means make someone appear guilty of committing a crime, and “vindicate” is a verb that can mean remove blame or suspicion from someone. “Incriminate” and “vindicate” are thus antonyms, or opposites, and we need to pick out an answer choice that consists of two verbs which are antonyms of each other. That means that neither “frighten is to terrify” nor “help is to assist” can be the correct answer, because each of those answer choices consists of a pair of synonyms, not antonyms. “Leave” is an antonym of “remain,” however, just as “incriminate” is an antonym of “vindicate,” so “leave is to remain” is the correct answer.

"Surge" is a verb that can mean a large and sudden increase while "plummet" is verb that can mean a large and sudden decrease. So, "surge" and "plummet" are antonyms, and we need to pick out an answer choice that consists of a pair of words that are antonyms. Because "catch" and "release" are the only pair of antonyms listed as a possible answer choice, "catch is to release" is the correct answer, because just as "surge" is the opposite of "plummet," "catch" is the opposite of "release."

“Ornate” is an adjective that means adorned with a complicated design, so “ornate” and “plain” are antonyms, or opposites, and we need to pick out an answer choice which also consists of two antonyms. While “conniving is to naive” and “dull is to uninteresting” might each look like a potentially correct answer, “dull” is an adjective that can mean boring, so it is a synonym, not an antonym, of “uninteresting,” and “dull is to uninteresting” cannot be the correct answer. “Conniving,” however, is an adjective that means conspiring to accomplish bad things, while “naive” can mean innocent when describing a person. So, because “conniving” is an antonym of “naive” just as “ornate” is an antonym of “plain,” “conniving is to naive” is the correct answer.

Since "ravenous" means very hungry and "satiated" means very full, the two words are antonyms. So, we need to pick out an answer choice in which the two words are opposites. While "nimble is to spry" might look like a good answer, "nimble" means agile and "spry" means lively and agile, the two words are synonyms, so "nimble is to spry" cannot be the correct answer. "Facetious is to serious," however, consists of a pair of antonyms: "facetious" means flippant and not treating important issues seriously. Because "facetious" is an antonym of "serious" just as "ravenous" is an antonym of "satiated," "facetious is to serious" is the correct answer.

"Volatile" means unstable or dangerous and is an antonym of "stable," which means reliable or unvarying. To solve this analogy, you have to determine the best antonym of "boisterous." "Boisterous" means loud, wild, and energetic, so the best antonym is “calm,” which means peaceful or tranquil. For clarification, "lively" and "energetic" both mean full of energy, "challenging" means presenting difficulties, and "unstable" means unsteady or likely to change.

"Inflate" means to swell up or fill with air while "deflate" means to reduce or release air from. They are antonyms, just like “suitable” and “unsuitable.” To further help you, “credible” means easy to believe or information you can rely on; “conform” is to become similar or the same; “suited” means appropriate, fitting. 

If someone is “deceptive," they are dishonest, so "deceptive" and "honest" are antonyms because they have opposite meanings. The opposite of “humble,” which means not proud, is “arrogant,” which means proud and feeling superior. To clarify the other terms, “oblique” means not direct or not straightforward; “typical” means commonplace; “mumble” means to talk quietly or unclearly.

"Colossal" is an adjective that means "very big," and "minuscule" an adjective that means "very small," so the two words are antonyms, or opposites, and we need to pick out another pair of words that are also antonyms. Because "night is to day" is the only answer choice in which the two words are opposites, "night is to day" is the correct answer.