_____ is known to everybody, the moon travels round the earth once every month.

A. It            B. As?               C. That             D. What

 _____ is known to everybody, the moon travels round the earth once every month.

A. It    B. As        C. That       D. What

________is known to everybody, the moon travels round the earth once every month.

A. It B. As

C. That D. What

________ is known to everybody, the moon travels round the earth once every month.

A. It　　　 　　　　　　　　　　 B. As

C. That　　　 　　　　　　　 D. What

_____ is known to everybody, the moon travels round the earth once every month.

A. It　　　　　　　　　　　 B. As

C. That　　　　　　　　　　 D. What