In her first class, her professor asked her and her classmates _________ impresses them most when it

In her first class, her professor asked her and her classmates _________ impresses them most when it comes to Arica.
A. how B. what
C. which D. that
【答案】B
【解析】
【详解】考查宾语从句。句意：在她的第一堂课上，教授问她和她的同学们，当谈到阿里卡时给他们留下了最深刻印象的是什么。表示“……的东西”用what引导宾语从句，故选B.