You work as a database administrator for Certkiller .com. You want to create your database with the automatic undo management feature enable.Which two tasks must you perform to achieve this？（）

A

Set the UNDO_RETENTION parameter to AUTO.

B

Create an initial undo segment in undotablespace.

C

Set the UNDO_RETENTION parameter to 900 or more

D

Set the initialization parameter UNDO_MANAGEMENT to AUTO

E

Set the UNDO_MANAGEMENT parameter to the name of an undotablespace