Which two statements are true regarding SecureFile lobs?

A.
The amount of undo retained is user controlled.

B.
They can be used only for nonpartitioned tables.

C.
Fragmentation is minimized by using variable-sized chunks.

D.
They support random reads and writes of encrypted LOB data.

Explanation:
http://docs.oracle.com/cd/E11882_01/appdev.112/e18294/adlob_smart.htm#ADLOB46113