—I do believe the scientific explanation that when a tomb is opened, the fresh air disturbs the viruses inside it. What about you?

—So do I. If _______ in, the disturbed viruses may cause illness or even death.

A．breathing

B．breathed

C．being breathed

D．to breathe

在采石场运输石头应事先检查汽车车况，如方向、刹车，临近拐弯处须鸣笛。