As we often see,some people work best in tasks alone,____ others work best in groups.

题目

As we often see,some people work best in tasks alone,____ others work best in groups.
A.when B.since C.while D.because
答案选C,我想知道A为什么不可以

答案

While有“然而”的意思,较长用,虽然字典里when也有“然而”的意思,但不常见,要慎用