We haven’t settled the question of it is necessary for him to study abroad. A. ifB. where

问题补充：

We haven’t settled the question of it is necessary for him to study abroad.

A. if

B. where

C. whether

D. that

答案：

A. if

B. where

(答案→)C. whether

D. that

解析：根据句意，空格处应填一个表示“空格处应填一个表示是否”的词，但在A和C两个表示“是否”的选项中，if不能用于介词后，故选C。