Maria has written two novels, both of ________ have been made in

Maria has written two novels, both of ________ have been made into television series.
A、them
B、that
C、which
D、what
【正确答案】：C
【题目解析】：此处先行词是two novels，后面是一个非限制性定语从句且介词前置，因此用both of which引导。句意：Maria写了两部小说，两部都被拍成了电视剧。【考点】考查非限制性定语从句的用法。