Which SQL statement would produce the required result?

See the Exhibit and Examine the structure of the CUSTOMERS table:

Using the CUSTOMERS table, you need to generate a report that shows an increase in the credit limit by 15%
for all customers. Customers whose credit limit has not been entered should have the message “Not Available”
displayed.
Which SQL statement would produce the required result?

A.
SELECT NVL(cust_credit_limit,’Not Available’)*.15 “NEW CREDIT” FROM customers;

B.
SELECT NVL(cust_credit_limit*.15,’Not Available’) “NEW CREDIT” FROM customers;

C.
SELECT TO_CHAR(NVL(cust_credit_limit*.15,’Not Available’)) “NEW CREDIT” FROM customers;

D.
SELECT NVL(TO_CHAR(cust_credit_limit*.15),’Not Available’) “NEW CREDIT” FROM customers;

Explanation:
NVL Function
Converts a null value to an actual value:
Data types that can be used are date, character, and number.
Data types must match:
NVL(commission_pct,0)
NVL(hire_date,’01-JAN-97′)
NVL(job_id,’No Job Yet’)