Which statement is true regarding the outcome of the above query?

Evaluate the following SQL statement:

Which statement is true regarding the outcome of the above query?

A.
It executes successfully and displays rows in the descending order of
PROMO_CATEGORY.

B.
It produces an error because positional notation cannot be used in the order by clause
with set operators.

C.
It executes successfully but ignores the order by clause because it is not located at the
end of the compound statement.

D.
It produces an error because the order by clause should appear only at the end of a
compound query-that is, with the last select statement.