[求助]大全-I-18

18. Critics of sales seminars run by outside consultants point out that since 1987, revenues of vacuum cleaner companies whose employees attended consultant-led seminars were lower than revenues of vacuum cleaner companies whose employees did not attend such seminars. The critics charge that for vacuum cleaner companies, the sales seminars are ill conceived and a waste of money.

Which of the following, if true, is the most effective challenge to the critics of sales seminars?

(A) Those vacuum cleaner companies whose sales were highest prior to 1987 are the only companies that did not send employees to the seminars.

(B) Vacuum cleaner companies that have sent employees to sales seminars since 1987 experienced a greater drop in sales than they had prior to 1987.

(C) The cost of vacuum cleaner sales seminars run by outside consultants has risen dramatically since 1987.

(D) The poor design of vacuum cleaner sales seminars is not the only reason for their ineffectiveness.

(E) Since 1987, sales of vacuum cleaners have risen twenty percent.

答案是A, 错了两次了. 请求指教. 这个题目到底关键在哪里啊???偶选的是C.

Pumpkin MM,     原文逻辑：参加seminar的收入没有不参加seminar的多-->seminar无效；

C说咨询费贵是化的多．比如你去年挣了5000元，化了2000元．今年物价涨了，你挣了1000元，化了9000元．可是你的收入还是增长了．和物价上涨无关．

A说在1987年以前，就是那帮不参加seminar的多，可能参加seminar的公司相对于自己以前多了，可是还是没有弥补上以前和不参加seminar的差距

    weiyu兄的逻辑思路很清晰，佩服！！

    这个题目就类似于一个servey，之前所选的比较对象存在差异。。。（我已将其归类于一种通用的错误）

偶把那个C理解成sales-cost=profit(revenue)了

嗯, 就是说, A是指出了那些没有采用SEMINAR的公司原来就是有销售好, 那么那些采用的公司即使采用了, 也还是没有追上, 但是说SEMINAR有负面作用是the sales seminars are ill conceived and a waste of money. 就削弱了
谢谢讲解

对对, 这里dreadpower说的更好理解了....

多谢