Asia has achieved more in controlling the bird flu than Europe in the past few years th

问题补充：

Asia has achieved more in controlling the bird flu than Europe in the past few years,

the number of people infected with the virus is going up sharply.

A. when

B. that

C. so that

D. where

答案：

A. when

B. that

C. so that

(答案→)D. where

解析：本题易误选A。where引导的是非限制性定语从句，以说明欧洲在控制the bird flu病毒方面的情况，从而与亚洲形成对比。