关于类比加强的选项的问题，求NN指导

Gracezhang-

搜了CD没有搜到类似问题，求NN指导，很迷惑

A new commercial radio station in Greenfield plans to play songs that were popular hits fifteen to twenty-five years ago. It hopes in this way to attract an audience made up mainly of people between thirty-five and forty-five years old and thereby to have a strong market appeal to advertisers.

Each of the following, if true, strengthens the prospects that the radio station's plan will succeed EXCEPT：

A People tend to remain very fond of the music that they heard when they were in their teens and early twenties.  

B In a number of cities demographically similar to Greenfield, radio stations that play recordings of popular music from fifteen to twenty-five years ago have succeeded commercially.  

C People in the thirty-five- to forty-five-year-old age group are more likely to listen to the radio for news than for music.  

D The thirty-five- to forty-five-year-old age group is one in which people tend to have comparatively high levels of income and are involved in making household purchases.

E Among the few radio stations in the Greenfield area, there is none that plays music from this particular period for more than a few hours per week.

OA：C     也就是说B选项是可以加强的，这是一个通过类比来加强的选项。

但是另一道题却不选类比的选项来加强，

Last year a global disturbance of weather patterns disrupted harvests in many of the world’s important agricultural areas. Worldwide production of soybeans, an important source of protein for people and livestock alike, was not adversely affected, however. Indeed, last year’s soybean crop was actually slightly larger than average. Nevertheless, the weather phenomenon is probably responsible for a recent increase in the world price of soybeans.

Which of the following, if true, provides the strongest justification for the attribution of the increase in soybean prices to the weather phenomenon?

A, Last year’s harvest of anchovies, which provide an important protein source for livestock, was disrupted by the effects of the weather phenomenon.

B, Most countries that produce soybeans for export had above-average harvests of a number of food crops other than soybeans last year.

C, The world price of soybeans also rose several years ago, immediately after an earlier occurrence of a similar global weather disturbance.

D, Heavy rains attributable to the weather phenomenon improved grazing pastures last year, allowing farmers in many parts of the world to reduce their dependence on supplemental feed.

E, Prior to last year, soybean prices had been falling for several years.

OA： A    我想知道不选C的原因

candycan123

EXCEPT题目里，ABDE虽然都是加强但是加强的有强有弱，下面那道题虽然问的是加强，但是其实你可以把它理解长解释这个矛盾，明明没受影响问什么价格还是上升了？因为GMAT默认的经济原理，如果产量降低价格会升高。你看C选项，只是说几年前出现过相同的状况，仅仅只是能加强这个现象是对的吧，有能解释为什么没受天气价格还升高了吗？而A就很好的解释了。个人看法~

Gracezhang-

candycan123 发表于 2017-6-26 15:33
EXCEPT题目里，ABDE虽然都是加强但是加强的有强有弱，下面那道题虽然问的是加强，但是其实你可以把它理解长 ...

谢谢~我觉得有道理的！！！

蟹黄味蚕豆

两道题看起来很相似，但实际上在推理方式上是完全不同的。
第一道题是因果推理，就是说，我有了因，我来预测果。在这种情况下，我有一个平行的例证，是可以加强我的这种因果关系的。
但是第二题，是一个果因推论，题目问的是大豆价格的上涨是不是有天气的现象导致的，这个时候你增加一个平行例证，其实无益于说明大豆价格上涨是由天气现象导致的。
为什么呢？
第一道题，A→B，要加强，也就是说A是B的充分条件。
而第二道题，反过来了B←A，要说的是A是B的必要条件。
所以在第一题中，我举了一个平行例证，说明A就是B的充分条件，就加强了论证。
而第二题，我说A是B的充分条件，你用充分来证明必要，这个就是不能够加强的。
如果说前面太抽象了，我们来举个例子：
比如说
1.论证的是：小明吃多了，他就会胖。 平行例证：小王跟小明各方面都一样，小王吃多了就胖了。 这个没问题，加强了。
2.论证的是：小明变胖了，是因为他吃多了。 平行例证：小王跟小明各方面都一样，小王吃多了就胖了。
但是小明变胖了，可能是因为没有运动，可能是因为遗传，而不能是因为吃多了会导致胖，而将变胖全部归因于吃多了。

再回题目，E选项的问题，如同OG中说的一样，只是说两件事情同时发生了，而并没有说是谁导致了谁。
如果说选项，改成：上一次大豆价格的上涨，也是由类似的天气现象导致的，那么其实就是可以加强文章中的论证。