Which two are prerequisites for performing a flashback transaction? (Choose two.) 

Answer options:

A. Flashback Database must be enabled.
B. Undo retention guarantee for the database must be configured.
C. EXECUTE privilege on the DBMS_FLASHBACK package must be granted to the user flashing back transaction.
D. Supplemental logging must be enabled.
E. Recycle bin must be enabled for the database.
F. Block change tracking must be enabled tor the database.

BD

References: http://searchoracle.techtarget.com/tip/How-to-perform-Oracle-Flashback-Transaction-Queries https://docs.oracle.com/cd/E11882_01/appdev.112/e41502/adfns_flashback.htm#ADFNS610