H Company's merchandise inventory account shows an ending inventory balance of $30,100 at the year end and a physical inventory count indicates inventory balance of $30,000 on hand. What are the adjusting entries?

a. Debit Cost of goods sold $100; and Credit Accounts payable $100

b. Debit Purchase expense $100; and Credit Cost of goods sold $100

c. Debit Merchandise Inventory $100; and Credit Cost of goods sold $100

d. Debit Cost of goods sold $100; and Credit Merchandise Inventory $100