You plan to execute the following command to perform a Flashback Database operation in your database：   SQL> FLASHBACK DATABASE TO TIMESTAMP （SYSDATE -5/24）；   Which two statements are true about this？（）

• A、 The database must have multiplexed redo log files
• B、 The database must be in the MOUNT state to execute the command
• C、 The database must be in the NOMOUNT state to execute the command
• D、 The database must be opened in RESTRICTED mode before this operation
• E、 The database must be opened with the RESETLOGS option after the flashback operation