Europe has achieved more in controlling the AIDS virus than Asia in the past ten years th

问题补充：

Europe has achieved more in controlling the AIDS virus than Asia in the past ten years, the number people infected with the virus is going up sharply.

A. when

B. that

C. which

D. where

答案：

A. when

B. that

C. which

(答案→)D. where

解析：考查非限制性定语从句。where在句子中引导非限制性定语从句，修饰Asia。