PL/SQL quiz

The employee table contains these columns:
LAST_NAME VARCHAR2(50)
FIRST_NAME VARCHAR2(50)
SALARY NUMBER(8, 2)
You need to display the names of employees on more than an average salary of all employees.
Evaluate the SQL statement.
SELECT LAST_NAME, FIRST_NAME
FROM EMPLOYEE
WHERE SALARY < AVG(SALARY);
Which change should you make to achieve the desired results?

A. Change the function in the WHERE clause.
B. Move the function to the SELECT clause and add a GROUP clause.
C. Move the function to the SELECT clause and add a GROUP BY clause and a HAVING clause.
D. Use a sub query in the where clause to compare the average salary value.

Answer: [D]