Which two are true about flashback features in Oracle Database 19c and later releases? (Choose two.)

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Which two are true about flashback features in Oracle Database 19c and later releases? (Choose two.)

A. Flashback logs are automatically purged when DB_FLASHBACK_RETENTION_TARGET is set lower than the time they have already been retained.
B. Flashback logs are monitored and proactively deleted when beyond the retention period defined in DB_FLASHBACK_RETENTION_TARGET only after there is space pressure.
C. Flashback logs are monitored and proactively deleted when beyond the retention period defined in DB_FLASHBACK_RETENTION_TARGET before there is space pressure.
D. Flashback logs are monitored for being older than the retention period defined in DB_FLASHBACK_RETENTION_TARGET and can be deleted by an administrator written event trigger. E. Flashback logs are automatically purged whenever the value of DB_FLASHBACK_RETENTION_TARGET is changed.