Final answer:
The correct answer is D) proper segregation of duties between access to customer records and authorizing credit memos. This control is not specifically mentioned in the given options.
Step-by-step explanation:
The correct answer is D) proper segregation of duties between access to customer records and authorizing credit memos. This is because having proper segregation of duties is an important control to prevent the possibility of fraud or misuse of customer records. By separating the access to customer records from the authorization of credit memos, it helps ensure that credit memos are accurately issued based on valid reasons and not for unauthorized purposes.
On the other hand, the options A, B, and C are all important controls over credit memos. Proper segregation of duties to ensure that sales discounts taken were earned (option A) helps prevent fraudulent or unauthorized discounts. Having credit memos approved by someone other than the initiator (option B) adds an extra layer of review and reduces the risk of errors or abuse. Credit memos supported by a receiving document for returned goods (option C) provide evidence that the return actually took place and helps prevent false or unauthorized credits.