You have an obligation to pay $1,488 in four years and 2 months. In which bond would you invest your $1,000 to accumulate this amount, with relative certainty, even if the yield on the bond declines to 9.5% immediately after you purchase the bond? A. a 6-year; zero-coupon bond B. a 5-year; 10% coupon bond C. a 5-year; zero-coupon bond D. a 4-year; 10% coupon bond