(A) involves reasoning based on multiple causes for a single effect. But the stimulus’s reasoning involved the claim that something was necessary for another thing. This is different from an argument based on multiple causes.

This matches the structure: we can’t conclude X based merely on Y, because X also requires Z. We can’t conclude the plant will bloom based merely on the fact it gets lots of sunlight each day, because blooming also requries slightly alkaline soil.

(C) involves an argument designed to show that we can’t conclude one thing caused an effect, because there are reasons to think that cause wouldn’t produce the effect. This isn’t parallel to an argument based on presenting a necessary condition for something.

(D) involves an argument designed to prove that having multiple things that meet a necessary condition does not make something more likely to happen than having only one thing that meets a necessary condition. This isn’t parallel to the stimulus, which didn’t involve a comparison between having multiple things that meet a necessary condition vs. only one thing.

This is close, but the structure here is “We can’t conclude X based only on evidence of Y, because X requires Y to be present for a long time.” (E) doesn’t involve the assertion that there’s an additional necessary condition that must be met — rather, it’s based on the claim that the evidence of the necessary condition (high blood pressure) needs to be seen for a longer time (we need to see chronically high blood pressure).