大全-I-18，求解答

hao0579

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，思路上似乎跟上了A的逻辑，但是A选项的句子不太明白，求细解~~谢谢！

kobegibson

A说 就是只有最牛的那家洗尘器公司没派人参加讨论会.

等于说有一天全联盟人都训练了就乔丹一个人没训练,结果还是谁都打不过乔丹,不能说训练没用.

hao0579

谢谢，明白了