单选题________he was a rising&n

单选题 ________he was a rising film star in China, but now few young people know him.A.At a timeB.All the timeC.At one timeD.At times

C解析这题考查词组：At a time一次，.All the time一直，.At one time曾经，At times有时，根据句意：他曾经是中国的崛起的电影明星，可是现在很少年轻人认识他，选C。

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