求助一道DWG逻辑题，没找到讨论

Vitacorp, a manufacturer, wishes to make
its information booth at an industry convention more productive in terms of
boosting sales. The booth offers information introducing the company’s new
products and services. To achieve the desired result, Vitacorp’s marketing
department will attempt to attract more people to the boost. The marketing
director’s first measure was to instruct each salesperson to call his or her
five best customers and personally invite them to visit the boost.

Which of the following, if true, most
seriously weaken the predication that the marketing director’s first measure
will contribute to meeting that goal of boosting sales?

A.      Customers who participate
booth are those not satisfied with Vitacorp products and will use
this opportunity to express their unsatisfaction.

B.       Many of Vitacorp’s competitors have made
plans for making their own information booths more productive in increasing
sales.

C.      An information booth that is well attended
tends to attract visitors who would not otherwise have attended the booth.

D.      Most of Vitacorp’s best customers also
have business dealings with Vitacorp’s competitors.

E.       Vitacorp has fewer new products and
services available this year than it had in previous years.

答案A，我选了B，哪位NN解释一下？

我也觉得B挺好，B很weaken，why not B?

期待NN解释