What could have helped you to correlate server sessions with channels?

Multiple RMAN sessions are connected to the database instance.
Examine the following output when backup commands are running in server sessions:

What could have helped you to correlate server sessions with channels?

A.
Implement RMAN multiplexing

B.
Set the DEBUG ON in the RMAN script

C.
Specify the command ID in the RMAN script

D.
Use a tag with the RMAN BACKUP command