第6题: [单项选择]The reason why the treasure from the sunken vessel disappeared was ______. A. that it had been washed away by the strong currents B. that the sand was unceasingly shifting C. unknown D. that it had been taken by those interested parties 参考答案:C 答案解析:由题干why the treasure disappeared定位到第二段最后一句“It is a mystery why and how the treasure disappeared,unkno