LOWER, UPPER

You want to display the details of all employees whose first names is Bill. But you are not sure in which case first names are stored. Which statement will list all the employees whose first name is Bill?
A. Select last_name, first_name FROM emp WHERE first_name= 'bill';
B. Select last_name, first_name FROM emp WHERE UPPER (first_name)= 'bill';
C. Select last_name, first_name FROM emp WHERE first_name = UPPER ('bill');
D. Select last_name, first_name FROM emp WHERE LOWER(first_name)= 'bill';

Answer:[D]
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