— When did you become a volunteer?

— Two years ago. I _____ this group since then. [ ]

A. joined

B. have joined

C. have been in

下列保险合同属于强制保险合同的是( )。

A．设计责任保险

B．安装工程一切险

C．建筑意外伤害保险

D．工程监理责任保险