单选题
Corporations should submit quarterly earning predictions and profit statements to news services because ______ should be easy for ordinary investors to track their activities.
(A) who
(B) it
(C) that
(D) they
【正确答案】
B
【答案解析】[语法] 代替to不定式主语的形式主语it [错误答案] 这道题容易将(D)they错当成正确答案。请记住从语意上讲，空白处应该填入可代替to不定式短语to track their activities的形式主语it。