She’s _________ is known as a nosy person — she is always dying to know what’s going on in others' lives.
A. what B. who C. which D. that
▲这道题没有错，且其答案只能是A，不能选B。你说的据“某资料”的分析是对，但没有讲清楚。who引导的名词性从句时表示“一个概念”，不是表示“一个人”。体会下面的句子：
1. Who will speak at the meeting is not known. 谁会在大会上发言还不清楚。
Who will speak at the meeting（谁会在大会上发言）在此为主语从句，它并非表示一个人，而是表示“谁会在大会上发言”这一概念。
2. I don’t know who is the leader. 我不知道谁是领导。
who is the leader（谁是领导）在此为宾语从句，它并非表示一个人，而是表示“谁是领导”这一概念。
3. The problem is who can be put in charge of the work. 问题是谁能来负责这项工作。
who can be put in charge of the work 在此为表语从句，它并非表示一个人，而是表示“谁能来负责这项工作”这一概念。
▲正因为who引导的名词性从句时表示“一个概念”，并非表示“一个人”，所以我们可以说：
The problem is who can be sent to replace him. 问题是能派谁去顶替他。
但不能说：
The man is who can be sent to replace him.（因为the man不可能是一个“概念”）
▲上面一题选 what，它在此相当于the person who。所以：
She’s what is known as a nosy person — she is always dying to know what’s going on in others' lives.
= She’s the person who is known as a nosy person — she is always dying to know what’s going on in others' lives. 她就是人们说的那种爱管闲事的人——总是千万百计地想知道别人生活中发生的事情。
又如：
He is no longer what he was. 他已经不是以前的他了。
He is what we call a “walking dictionary”. 他就是所谓的活字典。
He is what is generally called a traitor. 他就是人们通常所说的叛徒。