A company purchased 300 units for $20 each on January 31. It purchased 360 units for $24 each on February 28. It sold a total of 460 units for $40 each from March 1 through December 31. What is the cost of ending inventory on December 31 if the company uses the first - in, first-out (FIFO) inventory costing method? (Assume that the company uses a perpetual inventory system.) O A. $1,440 OB. $4,800 OC. $4,000 OD. $2,560