OG12第104求助

angelwings

104.
Although the discount stores in Goreville’s central shopping district are expected to close within five years as a result of competition from a SpendLess discount department store that just opened, those locations will not stay vacant for long. In the five years since the opening of Colson’s, a nondiscount department store, a new store has opened at the location of every store in the shopping district that closed because it could not compete with Colson’s.
Which of the following, if true, most seriously weakens the argument?

(A)
Many customers of Colson’s are expected to do less shopping there than they did before the SpendLess store opened.
(B)
Increasingly, the stores that have opened in the central shopping district since Colson’s opened have been discount stores.
(C)
At present, the central shopping district has as many stores operating in it as it ever had.
(D)
Over the course of the next five years, it is expected that Goreville’s population will grow at a faster rate than it has for the past several decades.
(E)
Many stores in the central shopping district sell types of merchandise that are not available at either SpendLess or Colson’s.
B正确。
请问牛人此题是什么逻辑啊？我感觉是在比较两个相似的案例，一个已经发生了，一个还未发生，题目用发生的结果来推断未发生的结果。因此，我们要weaken两者的关联性，但我实在看不出B怎么能weaken这种关联性。求牛人指点，不胜感激。

angelwings

非常感谢，终于想明白了。我觉得B中increasely是关键，它说明打折店在非打折店（Colson’s）存在时也能占据着市场份额，但如果S店出现后，这些打折店的市场份额都会被S店夺取，所有不会再有市场供新的打折店出现（非打折店已被C店消灭）。

sdcar2010

Google this forum. The question has been discussed many a time.