The BACKUP_TAPE_IO_SLAVES parameter is set to FALSE for the database instance. Which statement is true while performing a tape backup in an RMAN session？（）  

• A、 The tape I/O performed is asynchronous
• B、 The tape buffer is allocated from the System Global Area （SGA）
• C、 The tape buffer is allocated from the Program Global Area （PGA）
• D、 Oracle I/O uses an interrupt mechanism to determine when each I/O completes