问题补充：
--- Why did you leave the fan on in your room? It’s a waste of electricity. ---
A. I don’t think so, either.
B. Not at all .
C. Sorry, I will turn it off.
D. That’s all right.
答案：
A. I don’t think so, either.
B. Not at all .
(答案→)C. Sorry, I will turn it off.
D. That’s all right.
解析：句意，为什么你不关你房间的风扇?浪费电。C意思是，对不起，我会关。符合句子意思，故选C.
