He made another wonderful discovery,____ of great importance to science.
A.which I think is
B.which I think it is
C.which I think it
D.I think is
正确答案是A
He made another wonderful discovery,____ of great importance to science.
A.which I think is
B.which I think it is
C.which I think it
D.I think is
正确答案是A