Which of the following supplied functions is used to identify external tables, directories, and BFILES?

Which of the following supplied functions is used to identify external tables, directories, and
BFILES?

A.
DBMS_TDB.CHECK_DIRECTORIES

B.
DBMS_TDB.CHECK_EXTERNAL

C.
DBMS_TDB.CHECK_BFILE

D.
DBMS_TDB.CHECK_EXT