[求助]请教一道Conclusion题,谢谢!

Economist: Any country that is economically efficient will generate wealth. Such a country will remain politically stable only if that wealth is distributed equitably. The equitable distribution of wealth puts an end to risk taking, the indispensable precondition of economic efficiency.

Which of the following conclusions can be properly drawn on the basis of the statements above?

(A)No country can indefinitely remain both economically efficient and politically stable.

(B)No country can indefinitely remain both politically unstable and wealthy.

(C)Economic efficiency is the indispensable precondition for the generation of wealth in a country.

(D)Any country in which wealth is distributed equitably will indefinitely remain politically stable.

(E)Growing economic efficiency encourages risk taking, which in turn leads to further growth in economic efficiency.

正确答案是（A）,我想请问为何（C）不对呢?

谢谢!

我认为题目中说Any country that is economically efficient will generate wealth.表示economically efficient 是wealth的充分条件。

C中说Economic efficiency is the indispensable precondition for 表示Economic efficiency是wealth的必要条件。反了吧~