Canyoutellme makesthisbooksopopular?A

题目

Can you tell me_____makes this book so popular?
A.what is it which
B.what it is that
C.what it is which
D.what it is

优质解答

B.是什么使这本书如此畅销
what it is 是什么
that跟着前面是典型的强调句句型：it is ...that .