39题、choose two

　　You configured the Fast Recovery Area (FRA) for your database. The database instance is in ARCHIVELOG mode. The default location for the archived redo log files is the FRA.

　　Which two files are removed automatically if space is required in the FRA as per the retention policy?

　　A) user-managed backups of data files and control files

　　B) flashback logs

　　C) RMAN backups that are obsolete

　　D) archived redo log files that have multiple copies in a different archive location

　　Answer：BC

　　(解析：闪回区里面的数据如果是rman备份的数据，那么会根据冗余策略自动删除;还有闪回日志的保留时间由db_flashback_retention_target产生指定，如果超过了时间，则会自动删除。来自3组：1015267481)