问题
选择题
Besides the content of a book, ________ the editor also cares about is the number of readers.
A．who
B．why
C．how
D．what
答案
答案：D
D 考察名词性从句。句意：除来了书的内容，编辑还关心读者的数量。在句中________ the editor also cares about是主语从句，空格在从句中做care about的宾语，应该使用what作为引导词。故D正确。