User SCOTT wants to back out the transactions on the REGIONS table in his schema. As a DBA， which commands must you execute to enable SCOTT to flash back the transactions？（）

• A、 ALTER DATABASE FLASHBACK ON
• B、 GRANT SELECT any transaction TO scott
• C、 GRANT EXECUTE ON dbms_flashback TO scott
• D、 ALTER DATABASE ADD SUPPLEMENTAL LOG DATA
• E、 ALTER TABLESPACE undots1 RETENTION GUARANTEE
• F、 ALTER DATABASE ADD SUPPLEMENTAL LOG DATA （PRIMARY KEY） COLUMNS