On January 1 of the current year, Barton Corporation issued 10% bonds with a face value of $200,000. The bonds are sold for $191,000. The bonds pay interest semiannually on June 30 and December 31, and the maturity date is December 31, five years from now. Barton records straight-line amortization of the bond discount. The bond interest expense for the year ended December 31 is Oa. $18.000 Ob. $21.800 Oc. $10,900 Od, $29,000