Concept:Average stock is the mean value of inventory held during a period.Explanation:It is calculated by adding the opening stock and the closing stock, then dividing the total by two.Using the figures: opening stock = ₦32,000 and closing stock = ₦9,000.Average stock = 2opening stock+closing stockAverage stock = 232,000+9,000Average stock = 241,000=₦20,500Answer:A. ₦20,500