What may be the cause for the failure?

An administrator has a job that has failed. See the contents of the Job’s Detailed Status tab from the NetBackup Activity Monitor provided below:

What may be the cause for the failure?
A . The version of NetBackup installed on the master server and media server is higher than the version installed on the client.
B . The media server is unable to resolve the hostname of the client to any IP address.
C . The required NetBackup processes need to be started on the client.
D . The media server failed to perform a reverse name lookup of the IP address associated with the client.

Answer: A