求教大全上一个比较结构的题目

marschild

1.        A study commissioned by the Department of Agriculture showed that if calves exercise and associated with other calves, they will require less medication and gain weight quicker than do those raised in confinement.

(A) associated with other calves, they will require less medication and gain weight quicker than do

(B) associated with other calves, they require less medication and gain weight quicker than

(C) associate with other calves, they required less medication and will gain weight quicker than do

(D) associate with other calves, they have required less medication and will gain weight more quickly than do（E）

(E) associate with other calves, they require less medication and gain weight more quickly than

我选的是A~，但是条件句的主句不是应该用will表趋势吗？还有一点不明白就是if从句的结构，看起来像省略过的，但是我看不出来怎么弄的啊~最后那个比较句明明动词后面有接宾语嘛，prep都说这种不能省略助动词吧~

大家帮帮忙，谢谢

wenping0530

associate 应和exercise平行，所以可删除啊a, b,c