Consider a long forward contract to purchase a coupon-bearing bond whose current price is $456. The forward contract matures in 9 months and a coupon payment of $20 is expected in 4 months. Assume that the 4-month and 9-month risk-free continuously compounded interest rate are 3.5% and 4.25% per annum, respectively. Suppose the prevailing forward price is $500, what is the arbitrage profit?

a. $39.25 b. $49.64 c. $53.50 d. $61.25