Which internal control$($s$)$ would you recommend to prevent the following situations from occurring? LO $13-2$ a$.$ Authorization of a credit memo for a customer$$s account $($on receivables$)$ when the goods were never actually returned. b$.$ Theft of funds by the cashier, who cashed several checks and did not record their receipt. c$.$ Inventory was stolen by receiving dock personnel. The receiving clerk claimed the inventory was sent to the warehouse, but the warehouse clerk did not record properly. d$.$ Writing off a customer$$s accounts receivable balances as uncollectible in order to conceal the theft of subsequent cash collections. e$.$ Billing customers for the quantity ordered when the quantity shipped was actually less due to back$-$ordering of some items