题目内容：

___is obvious,the earth moves around the sun A.As B.It C.That D.What
___is obvious,the earth moves around the sun
A.As B.It C.That D.What
请说明理由
为什么不选B

优质解答

AIt is obvious that the earth moves around the sunAs is obvious 做伴随状语 表状态 这个地球围绕太阳的事实 是显然的ps.如果用it 就得改成：It is obvious that the earth moves around the sun...