Assuming a purchase on account not yet paid, a purchase return in a perpetual inventory system requires a

a/ debit to Accounts Payable and a credit to Merchandise Inventory.

b/ debit to Sales Revenue and a credit to Merchandise Inventory.

c/ debit to Cost of Goods Sold and a credit to Merchandise Inventory.

d/ debit to Sales Returns and Allowances and a credit to Accounts Receivable.