诚心求教GWD13-Q4 CR 香烟税后价和销售量

egretlee

In the years following an eight-cent increase in the federal tax on a pack of cigarettes, sales of cigarettes fell ten percent. In contrast, in the year prior to the tax increase, sales had fallen one percent. The volume of cigarette sales is therefore strongly related to the after-tax price of a pack of cigarettes.
The argument above requires which of the following assumptions?

A.    During the year following the tax increase, the pretax price of a pack of cigarettes did not increase by as much as it had during the year prior to the tax increase.
B.    The one percent fall in cigarette sales in the year prior to tax increases was due to a smaller tax increase.
C.    The pretax price of a pack of cigarettes gradually decreased throughout the year before and the year after the tax increase.
D.    For the year following the tax increase, the pretax price of a pack of cigarettes was not eight or more cents lower than it had been the previous year.
E.    As the after-tax price of a pack of cigarettes rises, the pretax price also rises.

答案是D, 但我怎么想都觉得这题模棱两可, 知道答案也没有恍然大悟的感觉, 其他几个选择比如B也有道理...

呼唤nn来帮忙。。。谢谢！！！

egretlee

谢谢哈!

篱笆下的青锋剑

已知：税升→香烟销量下降
求证：香烟税后价变化→香烟销量下降
所以，我们要的假设是：税升→香烟税后价变化，也就是税升→香烟税后价上升

看D选项，如果对D选项取反，即去掉not："the pretax price of a pack of cigarettes was eight or more cents lower than it had been the previous year”，那么导致的结果就是，税升之后的香烟税后价比之前的香烟税后价还低，这样的话当然不会造成销量下降。加上not，避免了这一情况，就有助于得出“香烟税后价变化→香烟销量下降”的结论。

其它选项都没有将“税升”和“香烟税后价上升”建立起联系。

yyt19

发错区了...这个应该去逻辑版