请教PREP逻辑一道

ltsysu

请教PREP逻辑一道，死活想不通。。。
Because postage rates are rising, Home Decorator magazine plans to maximize its profits by reducing by one half the number of issues it publishes each year. The quality of articles, the number of articles published per year, and the subscription price will not change. Market research shouws that neither subscribers nor advertisers will be lost if the magazine's plan is instituted.
Which of the following, if true, provides the strongest evidence that the magazine's profits are likely to decline if the plan is instituted?
A. With the new postage rates, a typical issue under the proposed plan would cost about one-third more to mail than a typical current issue would.
B. The majority of the magazine's subscribers are less concerned about a possible reduction in the quantity of the magazine's articles than about a possible loss of the current hgh quality of its articles.
C. Many of the magazine's long-time subscribers would continue their subscriptions even if the subscription price were increased.
D. Most of the advertisers that purchase advertising space in the magazine will continue to spend the same amount on advertising per issue as they have in the past.
E. Production costs for the magazine are expected to remain stable.
为什么A选项不对呢？

安徽民工

可能是这样，本题问的是利润下降的原因，应该从成本上升和收入减少方面入手。A说的是成本上升，D说的是收入减少。但是A中总邮寄数量下降一半，而单侧邮寄数量上升只有1/3，所以改革后的邮寄成本还是有所减少的，只不过减少的程度没有一半那么多，而D中的收入减少时确实的，所以选D。BCE属于打酱油选项。

ltsysu

明白啦，非常感谢~