Which two statements are true after enabling block change tracking on a physical standby database?

You are licensed to use Oracle Active Data Guard.
Which two statements are true after enabling block change tracking on a physical standby database?

A.
It allows fast incremental backups to be offloaded to the physical standby database.

B.
It starts the CTWR process on the physical standby database instance.

C.
It allows fast incremental backups to be taken on the primary database.

D.
It starts the RVWR process on the physical standby database instance.

E.
It allows fast incremental backups to be offloaded to a snapshot standby database, when the physical standby database in converted.

F.
It starts the CTWR process on the primary database instance.

Explanation:
A: Many of the customers now are opting to perform RMAN backups on standby database to offload the resources of production database.
B: To enable Active Data Guard on a standby database, set the ENABLE_OPTION_ACTIVE_DATA_GUARD initialization parameter to TRUE.
Note: Fast Incremental backups is possible with Block change tracking, which is initially introduced from version 10.2 onwards, by this tool it’s very useful to reduce
the RMAN incremental backup duration but it is limited only for Primary database. From 11g Oracle with Active Data Guard feature we can use Block change
tracking even on Physical standby database. T

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