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 答案选E。但是为什么不选D啊？D选项的partly because... 和原文的partly because crossbreeding不是更平行一些吗？ETS的解释说D选项罗嗦，有点搞不清楚。 | 
