OG th 紫色 22 求教！

22． In recent years cattle breeders have increasingly used crossbreeding，in part that their steers should acquire certain characteristics and partly because crossbreeding is said to provide hybrid vigor .

(A) in part that their steers should acquire certain characteristics

(B) in part for the acquisition of certain characteristics in their steers

(C) partly because of their steers acquiring certain characteristics

(D) partly because certain characteristics should be acquired by their steers

(E) partly to acquire certain characteristics in their steers

从平行结构的角度来讲：首先排除 A、B和C 项；

在D和E项时，仍然从平行结构考虑：partly + 句子 and partly + 句子结构！

当时做题的思路，首先从平行结构考虑，排除 A 、B 和 C项；

再次利用平行结构：partly + 句子 and partly + 句子 结构！

 所以得出答案 D

不过 AlienX 提到，选项D中的 should acquire， 似乎不正确！