We are now living in a high-tech age easy things are becoming complicated．A. whenB. thatC

问题补充：

We are now living in a high-tech age easy things are becoming complicated．

A. when

B. that

C. where

D. why

答案：

(答案→)A. when

B. that

C. where

D. why

解析：考查定语从句。先行词a high-tech age为从句的逻辑时间状语，故引导词用when，选A。