At school some students are active some are shy yet they can be good friends with one

问题补充：

At school, some students are active some are shy, yet they can be good friends with one another.

A. while

B. although

C. so

D. as

答案：

(答案→)A. while

B. although

C. so

D. as

解析：

试题分析:while ,然而，尽管。句意可知应为转折关系。故选A