Grey Enterprises Had Inventory on March 1 with a Cost

Grey Enterprises had inventory on March 1 with a cost of $6,000. During March, the company purchased additional inventory at a cost of $22,000. A physical count of the inventory at March showed goods at a cost of $4,000 on hand. What was Grey Enterprises' cost of goods available for sale for March?

A) $12,000
B) $22,000
C) $28,000
D) $32,000