There were two fantastic photos for the book, ________ was chosen as the front cover．

There were two fantastic photos for the book, ________ was chosen as the front cover．

A.one of them

B.both of them

C.one of which

D.all of which

答案及解析： C

解析：

句子后半部分是非限制性定语从句，由于从句中谓语是单数，而且只有两张照片，故选C项。