Answer is C. $42,506 please explain.

On January 1, 2016, Kathy Corp. leased equipment by signing a five-year lease that required five payments of $60,000 due on December 31 of each year. Kathy has a 9% cost of capital and capitalized the lease on January 1, 2016, in the amount of $233,379. As of December 31, 2016, what amount is reported as the current portion of the lease obligation?

a. $60,000 b. $46,331 c. $42,506 d. $13,669