Which three statements are true about using flashback database in a multitenant container database(CDB)?（）

• A、The root container can be flashed back without flashing back the pluggable databases (PDBs).
• B、To enable flashback database, the CDB must be mounted.
• C、Individual PDBs can be flashed back without flashing back the entire cdb.
• D、The DB_FLASHBACK RETENTION_TARGET parameter must be set to enable flashback of the cdb.
• E、A CDB can be flashed back specifying the desired target point in time or an SCN, but not a restore point.