[求助]急啊，快要考了~大家帮忙看看PREP上的题

32.

Paleontologist Jack has argued that many biological traits are not the product of natural selection ,favored because they enhance reproduction or survival ,but are simply random by-products of other evolutionary development.

A.because they enhance reproduction or survival ,but are

B.because they enhance reproduction or survival ,but

我不明白，为什么要选A呢？

are对么？不是not....but句型么？

21.

The publisher has announced  the creation of a new digital division ,under which it will publish about 20 digital works to be sold online as either electronic books or downloadable copies that can be printed upon purchase .

A.works to be sold online as either electronic books or
            

B.works tand it will sell them  online as either electronic books or
            

这道题做的时候不太明白为什么选B呢？

请NN解释一下~~谢谢啊~

32.

Paleontologist Jack has argued that many biological traits are not the product of natural selection ,favored because they enhance reproduction or survival ,but are simply random by-products of other evolutionary development.

A.because they enhance reproduction or survival ,but are

B.because they enhance reproduction or survival ,but

如果没有are了，but后面就不是一个句子了。

21.

The publisher has announced  the creation of a new digital division ,under which it will publish about 20 digital works to be sold online as either electronic books or downloadable copies that can be printed upon purchase .

A.works to be sold online as either electronic books or
            

to不定式修饰动词publish，publish的主语是it，所以to不定式的逻辑主语就是it（这样逻辑意思就不合理啦！）

B.works tand it will sell them  online as either electronic books or
            

The largest trade-book publisher in the United States has announced the creation of a new digital imprint division, under which it will publish about 20 purely digital works to be sold online as either electronic books or downloadable copies that can be printed upon purchase.

(A) works to be sold online as either electronic books or

(B) works to sell them online, either as electronic books or

(C) works and it will sell them online as either electronic books or as

(D) works, and selling them online as either electronic books or as

(E) works, and it will sell them online either as electronic books or

我的版本上答案为A 选项也有点出入 楼主再仔细检查一下

你给的版本中b项由于主语没变 it多余，而且没有信息说publisher把书给卖了 被卖了更好些，因为发出者并不明确