题目内容：
我在回答考试时的问题时非常紧张,以至于我的心里七上八下的。 [ 2 分 ] A. When I was answering the exam questions I was such nervous that I could feel butterflies in my stomach. B. When I was answering the exam questions I was so nervous that I could feel butters in my stomach. C. When I was answering the exam questions I was so nervous that I could feel butterflies in my stomach. D. I was answering the exam questions I was so nervous that I could feel butterflies in my stomach
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