OG2019 -Logical flow

GMATGuruNY wrote:

Mo2men wrote:Psychologist: In a study, researchers gave 100 volunteers a psychological questionnaire designed to measure their self-esteem. The researchers then asked each volunteer to rate the strength of his or her own social skills. The volunteers with the highest levels of self-esteem consistently rated themselves as having much better social skills than did the volunteers with moderate levels. This suggests that attaining an exceptionally high level of self-esteem greatly improves one’s social skills.

The psychologist’s argument is most vulnerable to criticism on which of the following grounds?

A. It fails to adequately address the possibility that many of the volunteers may not have understood what the psychological questionnaire was designed to measure.

B. It takes for granted that the volunteers with the highest levels of self-esteem had better social skills than did the other volunteers, even before the former volunteers had attained their high levels of self-esteem.

C. It overlooks the possibility that people with very high levels of self-esteem may tend to have a less accurate perception of the strength of their own social skills than do people with moderate levels of self-esteem.

D. It relies on evidence from a group of volunteers that is too small to provide any support for any inferences regarding people in general.

E. It overlooks the possibility that factors other than level of self-esteem may be of much greater importance in determining the strength of one’s social skills.

Premise:
Volunteers with the highest levels of self-esteem consistently rated themselves as having much better social skills than did the volunteers with moderate levels.
Conclusion:
Attaining an exceptionally high level of self-esteem greatly improves one’s social skills.

The correct answer must describe a FLAW -- a logical error that could serve to WEAKEN the conclusion.

It overlooks the possibility that X implies that X would WEAKEN the conclusion.
C: It overlooks the possibility that people with very high levels of self-esteem may tend to have a less accurate perception of the strength of their own social skills than do people with moderate levels of self-esteem.
The statement in green implies the following:
The volunteers in the study who had high self-esteem and rated themselves as having better social skills may not have accurately perceived the strength of their own social skills.
In other words, these volunteers may not actually HAVE better social skills, WEAKENING the conclusion that a high level of self-esteem can improve one's social skills.

The correct answer is C.

Mo2men wrote:Can you shed light on why B is wrong?