some of the middle-aged people___to the meeting were famous professors.

问题描述:

some of the middle-aged people___to the meeting were famous professors.
A who visited B visited

答案是B 能不能讲解下这里不用 who visited 的原因?

用B 是过去分词做后置定语 而如果是A 应该为who were visited否则定语从句成分残缺
用A people 和who表示的是一个意思,重复了