单选题 The parents were much kinder to their youngest child than they were to the others, ______, of course, made the others jealous.
A. which B. that C. what D. who

【正确答案】 A
【答案解析】本题测试非限定性定语从句的用法。本句缺少一个连接词，用来指代前面整个句子，在从句中做主语，故应选which。that不能引导非限定性定语从句；what不能引导定语从句；who是指代人，不能指代事物。