Which two statements are true about enabling write-back…

Which two statements are true about enabling write-back flash cache? (Choose two.)

A.
When enabling write-back flash cache in a non-rolling manner, it is important to ensure thatasmdeactivationoutcome is set to YES and asmModeStatus is set to ONLINE for all grid disks.

B.
Write-back flash cache requires a minimum required software version.

C.
Before write-back flash cache is enabled, you need to drop the Flash Cache first.

D.
The setting flashCacheMode should be set to Writeback by updating cellkey.ora and restarting cellsrv.

E.
When enabling write-back flash cache in a rolling manner, DBCLI should be used to inactivate the grid
disks on all cells first.

Explanation:
http://www.oracle.com/technetwork/articles/database/exadata-write-back-flash-2179184.html