—Do you miss your parents far away?

—Yes, very much. They _________ the hometown for over two years.

A．left

B．have left

C．were away from

D．have been away from

国家颁布的第一个专门规范劳动安全关系的法规是（）。

A.安全生产法

B.劳动法

C.矿山安全法