—What has happened in your hometown?

— Great changes _____ in my hometown recently.

A．have been taken place

B．have taken place

C．have been happened

D．was happened

调车作业中发生1辆货车脱轨，造成非繁忙干线线路单线或双线之一线行车中断6小时以上10小时以下的铁路交通事故，列为（）事故。

A.一般A类

B.一般B类

C.一般C类

D.一般D类