You plan to use static database registration for a new listener when you create it. What could be the two reasons for this？（）

A.More than one database is to be registered with the listener.

B.The users will connect the database by using the host naming method.

C.The Oracle Enterprise Manager is to be used to monitor an Oracle9i database.

D.The database that is to be registered with the listener is configured in shared server mode.

E.The listener is not configured on the default port of 1521 and the instance is not configured to register with a nondefault port.