She did more than __was required of her,__ satisfied her parents

D
有 more than 的时候，等于有了主语，后面选择which，是因为，
逗号前面整个都作先行词

所以，答案：D

感觉前面应该是what后面是which

what she省略了，which代前句

选D对么？？？别扭

是D
第一个空不能填that,
因为这里缺少的两个成分，
既要做这个从句的主语，*was required of her
也要做she did more than *的宾语，
而that作宾语可以，做主语就不行了，
that was required of her
不如what was required of her更合适

答案选项里没有这一项，
其实省略就可以的。
这是很常用的说法。