PSAT Reading Question 509: Answer and Explanation

Question: 509

Which option gives the best evidence for the answer to the previous question?

• A. Lines 10–11 ("Methanosphaera . . . methanogens")
• B. Lines 14–16 ("This explains . . . stadtmanae")
• C. Lines 21–23 ("Methanosphaera . . . bacteria")
• D. Lines 26–28 ("Methanogens . . . hydrogen")

Correct Answer: B

Explanation:

(B) Choice (B) is the correct answer because these lines explicitly state that the inability of Methanosphaera stadtmanae to reduce carbon dioxide to methane is what sets it apart from other methanogens. Lines 10–11 and 21–23 also give examples of differences among M. stadtmanae and other methanogens, but these lines don't mention any of the answers to the previous question. Choice (D) provides a similarity between M. stadtmanae and the other methanogens.