Question

The question _______ we can get enough coal for the winter has not been cleared up yet．

1. A.
   that
2. B.
   if
3. C.
   which
4. D.
   whether

Answer 1

D
本题考查同位语从句的引导词的用法。根据句has not been cleared up yet判断，此处使用whether，表示“是否”。