This is____I want to say.A all that B that C all what D which

问题描述:

This is____I want to say.A all that B that C all what D which
这题选A 还是选C啊 A是定语从句 C中 就是不清楚all作adj时可不可以接what.
选 C 怎么错了 all作形容词 what引导一个句子么。

Aall在这里做先行词,that 是定语从句.