auditor is concerned that fictitious sales have been recorded. The best audit procedure to identify the existence of the fictitious sales would be to a. select a sample of recorded invoices and trace to shipping documents (bills of lading) to b. select a random sample of shipping documents (bills of lading) and vouch to the sales invoice c. select a sample of customer purchase orders and trace through to the generation of a sale d. select a sample of invoices and vouch to a customer purchase order to determine whether a verify shipment of goods. to determine whether the invoice was properly recorded. invoice. valid customer actually exists