—Could you tell me how your mother usually goes to work?

—Yes. If it is fine, she ________ to her office.

A．will walk

B．will go on foot

C．walks

D．would go on foot

接发列车人员打盹，未及时开放进站信号，致使列车在站外停车，属于铁路交通一般（）事故。

A、A类

B、B类

C、C类

D、D类