PSAT Reading Question 95: Answer and Explanation

Question: 95

The author of Passage 1 refers to a paper by University of Chicago physicists Sidney Nagel and Thomas Witten (lines 17–23) primarily to

• A. imply that Nagel and Witten could have discovered the impact of ellipsoid particles.
• B. describe an impediment to research on suspended spherical particles.
• C. suggest that the study done by Nagel and Witten influenced the research by Yodh's team.
• D. contrast the results of earlier, flawed research with the useful data obtained more recently.

Correct Answer: C

Explanation:

C

The question asks why the author of Passage 1 mentions the paper by University of Chicago physicists Sidney Nagel and Thomas Witten. Use the given line reference to find the window. Lines 17–23 state that University of Chicago physicists Sidney Nagel, Thomas Witten, and their colleagues wrote an influential paper about this process in 1997, which focused mainly on suspended spherical particles, but it was not until the Yodh team's recent experiments that the surprising role played by suspended particle shape was discovered. It's clear that their paper was influential and that they used spherical particles, and their work preceded that done by Yodh's team. Look for an answer choice that matches this prediction. The passage doesn't mention any reason to think that Nagel and Witten could have discovered the impact of ellipsoid particles, so eliminate (A). Eliminate (B) because impediment means "obstacle," and Passage 1 doesn't indicate that Nagel and Witten's work in any way limited other studies. Choice (C) matches the prediction, so keep it. The passage does not state that their research was flawed, so eliminate (D). The correct answer is (C).