单选题 An analyst does research about gross profit margin and gathers the following information about a company in 2012:
·Average inventory is $2000
·Ending inventory of the year is $2500
·Total revenue is $20000
·Inventory tumover ratio is 5.5
·Tax rate is 40%
The gross profit margin for the company is closest to:
A. 27%
B. 31%
C. 45%

【正确答案】 C

【答案解析】[解析] inventory tumover ratio=cost of goods sold/average inventory
gross profit=revenue-cost of goods sold
gross profit margin=gross profit/revenue
所以，边际毛利率的计算如下：($20000-5.5×$2000)/$20000=45%。