We haven’t settled the question of __________ it is necessary for him to study abroad.
A. if B. where C. whether D. that
We haven’t settled the question of __________ it is necessary for him to study abroad.
A. if B. where C. whether D. that
C。
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。