When the effective interest method of amortization is used for a bond premium, the amount of interest expense for an interest period is calculated by multiplying the

a. carrying value of the bonds at the beginning of the period by the face interest rate.

b. face value of the bonds at the beginning of the period by the effective interest rate.

c. carrying value of the bonds at the beginning of the period by the effective interest rate.

d. face value of the bonds at the beginning of the period by the face interest rate