Suppose that the current risk-free bond yield is 4.5%. Which of the following risk-free bonds would have the lowest price?

a. 6.25% coupon bond, $100 face value, 3 years to maturity

b. 2.5% coupon bond, $100 face value, 8 years to maturity

c. 8.5% coupon bond, $100 face value, 10 years to maturity

d. 4.5% coupon bond, $100 face value, 12 years to maturity