150.You have enabled backup optimization in RMAN. You issue the following RMAN command to configure a redundancy-based retention policy: CONFIGURE RETENTION POLICY TO REDUNDANCY 3; Which statement is true?
A.The command fails because you cannot configure a redundancy-based retention policy when backup optimization is enabled
B.Backup optimization is performed, but RMAN considers the redundancy-based retention policy when it determines which datafiles should be backed up
C.Backup optimization is permanently disabled
D.Backup optimization is temporarily disabled because a redundancy-based retention policy is specified
正确答案是B