问题补充：
-- Why did you leave the fan on in your room? It’s a waste of electricity.
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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：I don’t think so, either.我也不这么认为；Not at all.一点也不；Sorry, I will turn it off.抱歉，我会把它关掉；That’s all right，那好吧。根据上文，你为什么让你的房间的电扇开着？——这是在浪费电。结合语境可知选C。
