_______ the moon moves round the earth is well known to all of u

_______ the moon moves round the earth is well known to all of us.
A、That
B、What
C、When
D、As
【正确答案】：A
【题目解析】：本题的考点是：That引导的主语从句，注意that引导的主语从句在句中只起到连接作用，没有意义，也不做任何成分。