Question ID:PT76 S4 Q21 Passage:At a large elementary school researchers studied a small group of children who successfully completed an experimental program in which they learned to play chess. The study found that most of the children who completed the program soon showed a significant increase in achievement levels in all of their schoolwork. Thus, it is likely that the reasoning power and spatial intuition exercised in chess-playing also contribute to achievement in many other areas of intellectual activity. Stem:Which one of the following, if true, most tends to undermine the argument? Correct Answer Choice:CChoice A:Some students who did not participate in the chess program had learned to play chess at home. Choice B:Those children who began the program but who did not successfully complete it had lower preprogram levels of achievement than did those who eventually did successfully complete the program. Choice C:Many of the children who completed the program subsequently sought membership on a school chess team that required a high grade average for membership. Choice D:Some students who did not participate in the chess program participated instead in after-school study sessions that helped them reach much higher levels of achievement in the year after they attended the sessions. Choice E:At least some of the students who did not successfully complete the program were nevertheless more talented chess players than some of the students who did complete the program.