Which SET operator would you use in the blank space in the following SQL statement to list the departments where all the employees have managers?

View the Exhibit and examine the structure of the EMPLOYEES and DEPARTMENTS tables.

Which SET operator would you use in the blank space in the following SQL statement to
list the departments where all the employees have managers?
SELECT department_id
FROM departments
SELECT department_id
FROM employees
WHERE manager_id IS NULL;

A.
UNION

B.
MINUS

C.
INTERSECT

D.
UNION ALL