In which situation does adding a referential constraint place a table space containing data into
check-pending status?

A.
When a primary key is defined on a table with no unique index.

B.
When a foreign key is defined on a table with the ENFORCED option.

C.
When a foreign key is defined on a table and a corresponding primary key has not been
defined.

D.
When a foreign key is defined on a table with NOT ENFORCED option and a unique index has
not been defined.

Explanation: