【题目】It's quite warm here; we __________turn the heating on yet.
A.couldn't
B.mustn't
C.needn't
D.wouldn't

【答案】C
【解析】句意：这里相当暖和，我们没有必要打开暖气。A. couldn't"不能"；B.mustn't"禁止"；C.needn't"不必"；D.wouldn't"不会"。根据上文“这里相当暖和”可以推知下文应该是：我们没必要开暖气。故选C。