Porter Corp. purchased its own par value stock on January 1, 2010 for $20,000 and debited the treasury stock account for the purchase price. The stock was subsequently sold for $12,000. The $8,000 difference between the cost and sales price should be recorded as a deduction from
a. additional paid-in capital to the extent that previous net "gains" from sales of the same class of stock are included therein; otherwise, from retained earnings.
b. additional paid-in capital without regard as to whether or not there have been previous net "gains" from sales of the same class of stock included therein.
c. retained earnings.
d. net income.