Identify two correct statements about multitenant architectures.()
A、Multitenant architecture can be deployed only in a Real Application Clusters (RAC) configuration.
B、Multiple pluggable databases (PDBs) share certain multitenant container database (CDB) resources.
C、Multiple CDBs share certain PDB resources.
D、Multiple non-RAC CDB instances can mount the same PDB as long as they are on the same server.
E、Patches are always applied at the CDB level.
F、A PDB can have a private undo tablespace.