Not having seen linda for many years,l find she is not the girl( )she used be

问题描述:

Not having seen linda for many years,l find she is not the girl( )she used be
A.who B.whom C.that D.which
我想知道为什么B不行啊

She used to be that person.= She used to be that.可以用that替换that person that是“那个人”;而whom是“谁”,词义错误.不能说:She used to be whom.