-May we leave the classroom now?

-No, you ______. You ______ to leave until the bell rings.

A．mustn’t, are allowed

B．don’t have to, are supposed

C．needn’t, aren’t allowed

D．can’t, aren’t supposed

依照行为的客观性和法律的规定性而必然认定的商行为是（）。

A.相对商行为

B.绝对商行为

C.双方商行为

D.基本商行为