Which two are prerequisites for enabling Automatic Block Media Recovery in a Data Guard environment consisting of a primary database, one physical standby database and one logical standby database? 

Answer options:

A. FLASHBACK DATABASE must be enabled on the physical standby database.
B. There must be connectivity between the primary and the physical standby database.
C. FLASHBACK DATABASE must be enabled on the primary database.
D. The physical standby database must have Real-Time Apply enabled.
E. The logical standby database must have Real-Time Query enabled.

CD

C: Flashback Database must be enabled on the target database for RMAN to search the flashback logs for good copies of corrupt blocks. You must have already enabled Flashback Database on the original primary database before the failover. D: Block media recovery is a technique for restoring and recovering corrupt data blocks while data files are online. If only a few blocks are corrupt, then block media recovery may be preferable to data file media recovery. For automatic block media recovery to work, a physical standby database must be in real-time query mode, which requires an Oracle Active Data Guard license. References: https://docs.oracle.com/cd/E11882_01/server.112/e41134/scenarios.htm https://docs.oracle.com/database/121/BRADV/rcmblock.htm#BRADV89786