Read this excerpt from "the destructors" by graham greene and answer the question that follows: "blackie lumbered nearer the saw and the sledge-hammer. perhaps after all nobody had turned up; the plan had been a wild invention; they had woken wiser. but when he came close to the back door he could hear a confusion of sound hardly louder than a hive in swarm; a clickety-clack, a bang bang bang, a scraping, a creaking, a sudden painful crack. he thought; it’s true, and whistled." why is confusion an effective choice?

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? (a) as people grow older, they are often advised to keep exercising their physical and mental capacities in order to maintain or improve them. (b) many medical conditions and treatments that adversely affect a person's mental sharpness also tend to increase that person's social isolation. (c) many people are proficient both in social interactions and in solving mathematical problems. (d) the study did not itself collect data but analyzed data bearing on the issue from prior studies. (e) the tasks evaluating mental sharpness for which data were compiled by the study were more akin to mathematics problems than to conversation.