The net amount required to retire a bond before maturity (assuming no call premium and constant interest rates) is the:
a. issuance price of the bond plus any unamortized discount or minus any unamortized premium.
b. face value of the bond plus any unamortized premium or minus any unamortized discount.
c. face value of the bond plus any unamortized discount or minus any unamortized premium.
d. maturity value of the bond plus any unamortized discount or minus any unamortized premium.