Questions 138-139 are based on the following.

Roland: The alarming fact is that 90 percent of the people in this country now report that they know someone who is unemployed.

Sharon: But a normal, moderate level of unemployment is 5 percent, with 1 out of 20 workers unemployed. So at any given time if a person knows approximately 50 workers, 1 or more will very likely be unemployed.

139.

Sharon's argument relies on the assumption that

(A) normal levels of unemployment are rarely exceeded

(B) unemployment is not normally concentrated in geographically isolated segments of the population

(C) the number of people who each know someone who is unemployed is always higher than 90% of the population

(D) Roland is not consciously distorting the statistics he presents

(E) knowledge that a personal acquaintance is unemployed generates more fear of losing one's job than does knowledge of unemployment statistics

B is the best answer.

If normal levels of unemployment were exceeded relatively frequently, and if Roland’s figure of 90 percent were an exaggeration, Sharon’s argument would be unaffected, so choices A and D are incorrect.

dont understand how would S's argument would be unaffected?

頭腦一時有點轉不過來

刚才搜索了一下，论坛里好像没有人回答过这个问题呀。

我也不明白，请指教^_^

推理过程：虽然有90%的人都认识失业的人，但是因为5%的适当失业率，如果一个人认识50个人，就会至少有1个或者更多的人失业的。

答案：失业人不会集中的住在一起，即调查方法有效性。

Assumption答案类型：排除他因