Simpana Client Failed to the Perform Backup Task

Multiple Choice

Simpana client failed to the perform backup task.  When you view the task status, it reports the following error: libary mediaagent drive pool media []: Mount path is offlline advice: please check if the mount path is online and accessible " What can cause this?

A) Client offline
B) Media Server Offline
C) The client can not resolve the media server host name
D) backup media failure