首先否定一下楼上那位的说法,这儿的who不是you think的宾语.
“_____ you think is pleased to ____”是定语从句,首先这儿的you think 是插入语,可以去掉不看,变成“_____ is pleased to_____”,所以佷显然宾语从句中缺的是主语,而指人且充当主语的只能是who.那么只能在A和B中选,再根据词组work with,所以选B.
如果选A的话,后面还要跟with或者to.