单选题 Jane Higgins, CFA, a industry analyst, does research about inventory valuation. The company uses a periodic inventory system and no inventory on 31 May, 2012. The company purchases inventory as follows:

Purchase Date	Cost per Unit	Number of Units
1 May	$14.00	1000
3 May	$10.00	400
6 May	$8.00	1500
23 May	$10.00	300

During May, 2000 units are sold. Under the weighted average cost method of inventory valuation, cost of goods sold is closest to:
A. 20160
B. 20625
C.