Which Oracle-supplied package is used by Data Pump Export and Import worker processes to load and unload metadata information?

Which Oracle-supplied package is used by Data Pump Export and Import worker processes to load and unload metadata information?

A.
DBMS_STREAMS_DATAPUMP_UTIL

B.
DBMS_METADATA_UTIL

C.
DBMS_METADATA

D.
DBMS_STREAMS_DATAPUMP

E.
DBMS_DATAPUMP