—Doesn’t he feel       impolite when he laughs with his mouth full of food?

—I will ask him to pay attention to his behavior.

A．it

B．that

C．this

D．these

对于通用航空飞行任务的飞行预报，有关管制室应当不迟于飞行开始前（）前批复。

A.一日的15：00

B.一日的12：00

C.一日的20：00