Data below for the year ended December 31, 2015, relates to Bamboo Inc. Bamboo started business January 1, 2015, and uses the LIFO retail method to estimate ending inventory. Beginning inventory Cost $66,000, Retail $104,000. Net purchases Cost $280,000, Retail $420,000. Net markups $20,000. Net markdowns $40,000. Net sales $375,000. Estimated ending inventory at cost is A. $91,600 B. $90,720 C. $67,650 D. $83,500