— What have you done these days?
— I’ve read all the books you gave me because they are the best ones are on the subject.
A. that; that
B. which; which
C. what; which
D. who; what
网友回答
(答案→)A. that; that
B. which; which
C. what; which
D. who; what
解析：考察定语从句。当先行词是指物且前面有all和形容词最高级修饰的时候，都是使用关系代词that。故Ａ正确。