Some amazing people our world for the better in the past 100 years.A. changeB. are changi

问题补充：

Some amazing people our world for the better in the past 100 years.

A. change

B. are changing

C. have changed

D. had changed

答案：

A. change

B. are changing

(答案→)C. have changed

D. had changed

解析：表示过去的某一动作或行为一直持续到现在，用现在完成时，故选C。