The current price of a stock is $50 and the annual risk-free rate is 8 percent. A call option with an exercise price of $55 and one year until expiration has a current value of $7.20. What is the value of a put option (to the nearest dollar) written on the stock with the same exercise price and expiration date as the call option? (Use put-call parity)

a. $6.00

b. $5.00

c. $8.00

d. $7.00

e. $9.00