Elizabeth believed the dog would die if _____ to her cruel owners so she kept it.

A．returning

B．was returned

C．it would return

D．returned

OLT设备主要由业务接口模块、协议处理和控制模块、（）、电源及环境监控模块和光纤传输模块。

A.用户接口模块

B.系统管理模块

C.SIPP模块

D.时钟处理模块