You work as a database administrator for Supportcenter.cn. 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