295, Federally imposed restrictions on how much they may pay small savers has made difficulties for savings banks as they are competing with such unregulated investment vehicles as money market certificates.

(A) has made difficulties for savings banks as they are competing with such

(B) has made difficulties for savings banks competing with such

(C) have made difficulties for savings banks as they are competing with

(D) have made it difficult for savings banks to compete with such（B）

(E) have made it difficult for savings banks as they are competing with such [D]

请问d中的it指代的句中的哪个部分,没找到单数名词可以指代啊,还是指代的前面整个句子,thx

it 指代后面的to do 结构。

GMAT中，it不可以用来指代前面的整个句子(同which)，指代单数名词时，一般用that。

感觉make it difficult for sth to do这里it作为形式宾语指代后面的真正的宾

语for sth to do

 it 不能指代 for ....

因为it做形式宾语,它的词性必须是名词的词性,可以是名词性从句,不定式等等

但是介词短语是修饰语,它可以当形容词,可以当副词,就是不能当名词

所以我们习惯说的make it difficult to do sth/ that clause 都是可以的

 it 指代 to compete with such unregulated investment vehicles as money

market certificates.