Which two statements are true about the duplexing of the backups taken by RMAN? （）(Choose two.)

• A、It's only supported for the backups performed on the tape
• B、It is not supported for backup operations that produce image copies
• C、Duplex backups need a parallelism for the device to be equal to number of copies
• D、Duplex backups can be performed to either disk or tape, but cannot be performed on tape and disk simultaneously