LSAT-4-1--25（标题错误，lawyer改标题）

Because of the recent transformation of the market. Quore, Inc., must increase productivity, 10 percent over the course of the next two years, or it will certainly go bankrupt. In fact, however, Quore’s production structure is such that if a 10 percent productivity increase is possible, then a 20 percent increase is attainable.

If the statements above are true, which one of the following must on the basis of them also be true?

(A) It is only Quore’s production structure that makes it possible for Quore to survive the transformation of the market.

(B) Quore will not go bankrupt if it achieves a productivity increase of 20 percent over the next two years.

(C) If the market had not been transformed, Quore would have required no productivity increase in order to avoid bankruptcy.

(D) Because of the transformation of the market, Quore will achieve a productivity increase of 10 percent over the next two years.

(E) If a 20 percent productivity increase is unattainable for Quore, then it must go bankrupt.

E is the key, following is the explanation by someone in the forum.  

应该是 非A->B
其实，由条件1.Quore, Inc. must increase productivity, 10 percent over the course of the next two years, or it will certainly go bankrupt。中的‘OR“可以推出if not increase,it will go bankupt.that is  not A->B
由条件2 if a 10 percent productivity increase is possible, then a 20 percent increase is attainable 可以推出 10 percent increase will lead to a 20 percent increase. that is  A -> C ,not C-> not A,
conclude from 1 and 2,not C -> B

I don't quite agree with his second logic, the stems says "if 10% is possible, then 20% is attainable" does not necessarily mean 20% is a necessary condition for not being backruptcy, might just mean 20% is possible to achieve. I would choos C.

你的条件1为：if not increase by 10 percent, it will go bankupt.

条件2为： if 10% is possible, then 20% is attainable。逆否命题为：if 20% is unattainable, then 10% increase is impossible.

该逆否命题结合条件1就等于：if 20% is unattainable， then it will go bankrupt.即E。

C不会使答案，因为原文给的market transformation和公司是否破产是因果关系，不是充分必要关系。不可能推断出C的充分必要关系。