Exam 1z0-071 topic 1 question 208 discussion

Actual exam question from Oracle's 1z0-071

Question #: 208
Topic #: 1

Examine the description of the CUSTOMERS table:

For customers whose income level has a value, you want to display the first name and due amount as 5% of their credit limit. Customers whose due amount is null should not be displayed.

Which query should be used?

A. SELECT cust_first_name, cust_credit_limit * .05 AS due_amount

FROM customers -
WHERE cust_income_level IS NOT NULL
AND cust_credit_limit IS NOT NULL
B. SELECT cust_first_name, cust_credit_limit * .05 AS due_amount

FROM customers -

WHERE cust_income_level <> NULL -
AND due_amount <> NULL;
C. SELECT cust_first_name, cust_credit_limit * .05 AS due_amount

FROM customers -

WHERE cust_income_level != NULL -
AND cust_credit_level != NULL;
D. SELECT cust_first_name, cust_credit_limit * .05 AS due_amount

FROM customers -

WHERE cust_income_level != NULL -
AND due_amount != NULL;
E. SELECT cust_first_name, cust_credit_limit * .05 AS due_amount

FROM customers -
WHERE cust_income_level IS NOT NULL
AND due_amount IS NOT NULL;