单选题 A business has the following figures for the year ended 31 December 2000 ＄ Stock at beginning of period 85,000 Stock at the end of period 90,000 Purchases 300,000 Purchases return 25,000 Cost of goods sold is ______. (a)＄295,000 (b)＄270,000 (c)＄305,000 (d)＄280,000