Purrfect Pets uses the perpetual inventory system. At the beginning of the quarter Purrfect Pets has $30,000 in inventory. During the quarter the company purchases $7,900 of new inventory from a vendor, returned $700 of inventory to the vendor, and took advantage of discounts from the vendor of $200. At the end of the quarter the balance in inventory is $26,500. What is the cost of goods sold?

a. $10,500

b. $11,400

c. $3,500

d. $11,900