PSAT Reading Question 505: Answer and Explanation

Question: 505

What is the primary purpose of lines 39–40 ("it is . . . cells")?

• A. To address an objection
• B. To provide speculation
• C. To explain a process
• D. To cite an authority

Correct Answer: C

Explanation:

(C) Consider the context. Prior to these lines, the author stated that Methanosphaera stadtmanae is somehow connected to the occurrence of IBD. These lines serve to explain to the reader the role that M. stadtmanae plays in this process—it triggers the proinflammatory cytokines. Thus, he is explaining a process, choice (C). The answer isn't choice (A) because the author hasn't introduced any objections that he's trying to disprove. The answer isn't choice (B) because he's talking about a partially known scientific fact rather than a speculation. Choice (D) is incorrect because the author doesn't attribute this fact to anyone.