Saturated Quicksand
(A) Meaning / Idiom (so … as to)
(B) CORRECT
(C) Modifier (saturated with water enough)
(D) Meaning / Idiom (so as to)
(E) Meaning / Idiom (so … as to)
First glance
Three of the answer choices begin with that; consider Modifiers.
Issues
(1) Meaning / Idiom: so as to
According to the sentence, quicksand is sand that is saturated with water. Specifically, it is so significantly saturated with water that it becomes liquid-like. When using so to express that something has happened to a great degree, the correct idiom is so (adjective/adverb) that (independent clause). For example, the two sentences below are grammatically correct:
She studied so much that she got an 800 on the GMAT.
The yard was so overgrown with weeds that it took the gardeners five days to mow it.
Answer choices (A), (B), (D), and (E) use so. However, only one of them, choice (B), correctly uses the idiom so (adjective/adverb) that (independent clause). The remaining choices all inappropriately use the idiom so as to, which means in order to. This is not the intended meaning of the sentence, so eliminate choices (A), (D), and (E).
(2) Modifier: enough
The word enough can be used as either an adjective (enough pie to feed everyone) or an adverb (I ate enough for three people). When used as an adjective, enough almost always comes before the noun it modifies (saturated with enough water). When used as an adverb, enough generally appears immediately next to the verb it modifies (saturated enough with water). In this sentence, enough can logically be used as either an adjective or an adverb. However, it must appear in the correct position to serve as one of these two types of modifiers.
In answer choice (C), enough comes after water, so it cannot be an adjective, and it is not next to saturated, so it cannot be an adverb. Compare this to answer choice (D), in which enough correctly appears as an adverb next to saturated. Therefore, in answer (C), enough is not in the correct location to modify either water or saturated. Eliminate answer (C).
The Correct Answer
Correct answer (B) properly conveys the meaning with the idiom so … that. It also avoids incorrectly placing the modifier enough by not using the word at all.