Which two statements are true regarding undo tablespaces? (Choose two.)
A.
The UNDO_TABLESPACE parameter is valid in both automatic and manual undo
management
B.
Undo segments automatically grow and shrink as needed, acting as circular storage
buffer for their assigned transactions
C.
The database can have more than one undo tablespace
D.
An undo tablespace is automatically created if the UNDO_TABLESPACE parameter is
not set and the UNDO_MANAGEMENT parameter is set to AUTO during the database
instance start up