Official Verbal review 题目请教 （终于发帖成功）

首次发帖，编辑了无数次，才发现firefox不能用，换ie才成功。

1）请斑竹告知link去学习江湖切口，并请更改标题成江湖通用切口（缩写）

2) the official guide, GMAT Verbal review, p237第22题

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.
(D) partly because certain characteristics should be acquired by their steers
(E) partly to acquire certain characteristics in their steers

Answer
D Passive voice should be acquired by is awkward and illogical.
E Correct. In this sentence, the word partly is used to introduce both reasons; the phrase to acquire certain characteristics is clear and concise.

My question is why D is incorrect and why E is parallelism

lz查一下以往的讨论贴吧，OG的讨论贴很多很多，一般都能找到答案的。

如果还是不能解惑，再发贴也不迟。

这样解决问题的速度更快一些。

http://forum.chasedream.com/dispbbs.asp?boardID=23&ID=81938&page=1