30. The Sports Medicine Programs of the Olympic Training Center, a complex where final try outs are held for athletes representing the US in the Olympics, is geared toward enhancing athletes' performance and toward their preparation for international competition.

A.) is geared toward enhancing athletes' performance and toward their preparation

B.) is geared to enhance the performance of athletes and to prepare them
C.) are geared to enhance athletes performance and their preparation
D.) are geared toward the enhancement of athletes' performance and toward preparing them
E.)  are geared toward enhancing the performance of athletes and preparing them

A: is 应该改复数，toward 后面不平行

B: is 应该改复数

C: enhance their preparation 不合逻辑

D: and前后不平行

E: correct

注意：句意上判断是哪种平行

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我想知道为什么用are,而不是is, The Sports Medicine Programs of the Olympic Training Center 应该说的是一个大的项目吧？否则为什么要大写呢？

另外，enhance toword doing与enhance to do是否都可以使用，还是哪个更加好。。。

虽然是大写的，可是中心词是The Sports Medicine Programs 啊。说明不是一个program，是很多啊。

因为The Sports Medicine Programs of the Olympic Training Center 中心词是programs 啊

还有,这里并不是考enhance toword doing与enhance to do的区别,而是考 parallelism