Whatviewmightyouusetotrytodeterminehowlongaparticularbackupwilltake?()

Whatviewmightyouusetotrytodeterminehowlongaparticularbackupwilltake？（）

A、V$SESSION_EVENT

B、V$SESSION

C、V$WAITS

D、V$WAITSTAT

E、V$SESSION_LONGOPS