Final answer:
Under perpetual inventory systems, Purchase Discounts Lost is not a standalone account like Inventory, Cost of Goods Sold, or Sales, and is instead related to the purchase side of transactions.
Step-by-step explanation:
The question pertains to accounting practices under a perpetual inventory system. Under this system, a company continually updates its inventory records to reflect the merchandise on hand. When considering which of the listed accounts is not used under a perpetual inventory system, the correct answer is d. Purchase Discounts Lost. Unlike the other listed accounts such as Inventory, Cost of Goods Sold, and Sales, Purchase Discounts Lost is not typically a standalone account used in perpetual inventory systems because it relates more to the purchase side of transactions rather than inventory tracking.