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?

Question

Examsnet · Accepted Answer

Correct Answer is :  Those vacuum cleaner companies whose sales were highest prior to 1987 are the only companies that did not send employees to the seminars.

GMAT Verbal Reasoning Practice Test 3