题目选项分析

It is widely assumed that people need to engage in intellectual activities such as solving crossword puzzles or mathematics problems in order to maintain mental sharpness as they age. In fact, however, simply talking to other people——that is, participating in social interaction, which engages many mental and perceptual skills——suffices. Evidence to this effect comes from a study showing that the more social contact people report, the better their mental skills.

Which of the following, if true, most seriously weakens the force of the evidence cited?

【选项】The tasks evaluating mental sharpness for which data were compiled by the study were more akin to mathematics problems than to conversation.