If a Perpetual Inventory System Is in Use,which of the Following

If a perpetual inventory system is in use,which of the following statements about transactions with customers is correct?

A) When a customer pays within the discount period, Accounts Receivable is credited for the full amount.
B) If a customer pays within the discount period, Sales Discounts is credited.
C) A sales return is recorded with entries that include a credit to Sales Returns & Allowances.
D) Sales of inventory are recorded by entries that include a credit to Cost of Goods Sold.