A cash basis calendar year C corporation in Athens, Georgia, had $100,000 of accounts receivable on the date of its conversion to an S corporation on February 14. By the end of the year, $60,000 of these receivables had been collected. Calculate any built-in gains tax, assuming that there is sufficient taxable income.
a. $0.
b. $21,000.
c. $28,000.
d. $35,000.