On January 1, 2011, F Corp. issued 2,100 of its 8%, $1,000 bonds for $2,170,000. These bonds were to mature on January 1, 2021, but were callable at 101 any time after December 31, 2014. Interest was payable semiannually on July 1 and January 1. On July 1, 2016, F called all of the bonds and retired them. The bond premium was amortized on a straight-line basis. Before income taxes, F Corp.'s gain or loss in 2016 on this early extinguishment of debt was:

A. $17,500 gain.

B. $56,000 gain.

C. $10,500 gain.

D. $21,000 loss.