[单选题]Which statement is true about Enterprise Manager (

ABy default, EM express is available for a database after database creation.

BYou can use EM express to manage multiple databases running on the same server.

CYou can perform basic administrative tasks for pluggable databases by using the EM express interface.

DYou cannot start up or shut down a database Instance by using EM express.

EYou can create and configure pluggable databases by using EM express.