【题目】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】C
【解析】句意：我们还没解决是否他有必要出国学习的问题。介词of后面接的是宾语从句，从意思看，应该选whether。故选C。