He       to school, so he turned off the alarm clock and went back to sleep.

A．needn’t have gone

B．hasn’t needed to go

C．needn’t

D．didn’t need to go

下面说法正确的是

A．满足4范式不一定满足BC范式

B．满足BC范式一定满足4范式

C．满足4范式一定满足BC范式

D．BC范式与4范式没有任何关系