The Sino-U．S．relations, although they have experienced twists and turns(曲折)in the past, ________ hav

The Sino-U．S．relations, although they have experienced twists and turns(曲折)in the past, ________ have moved forward．

A.in return

B.in other words

C.on the whole

D.on the other hand

答案及解析： C