The young dancers looked so charming in their beautiful clothes that we took pictures of

问题补充：

The young dancers looked so charming in their beautiful clothes that we took pictures of them,

A. many of

B. masses of

C. the number of

D. a large amount of

答案：

A. many of

(答案→)B. masses of

C. the number of

D. a large amount of

解析：短语辨析。A.……当中的许多 B.大多数；大量的 C.……的数目D. 大量的，修饰不可数名词。句意：穿上他们漂亮的衣服，这些年轻的舞者看起来如此迷人，因此我们拍了大量的他们的照片。结合语境可知选B，为最佳答案。