In rencent years China and the USA have been a lot ofof views about the same problem. A.

问题补充：

In rencent years, China and the USA have been a lot ofof views about the same problem.

A. replacements

B. transformations

C. changes

D. exchanges

答案：

A. replacements

B. transformations

C. changes

(答案→)D. exchanges

解析：句意：近几年中美两国在相同的问题上交流了很多观点。exchange用作可数名词，意思为“交换；交流；互换”， exchanges of views交流观点。change改变或变更原有的东西或人,使之不同。replacement代替；取代；更换；transformation变化;转变;变形。