Consider an organization that sells products through a catalog and takes orders over the phone. All orders are entered online, and the organization’s objective is to ship all orders within 24 hours. The audit trail is kept in machine-readable form. The only papers generated are the packing slip and the invoice sent to the customer. Revenue is recorded upon shipment of the goods. The organization maintains a detailed customer database that allows the customer to return goods for credit at any time. The company maintains a product database containing all the authorized prices. Only the marketing manager has authorization to make changes in the price database. The marketing manager either makes the changes or authorizes the changes by signing an authorization form, and his assistant implements the changes. Which of the following controls would be least effective in assuring that the correct product is shipped and that it is billed at the approved price?

a. Self-checking digits are used on all product numbers, and customers must order from a catalog with product numbers.

b. The sales order taker verbally verifies both the product description and price with the customer before the order is closed for processing.

c. The sales order taker prepares batch totals of the number of items ordered and the total dollar amount for all items processed during a specified period of time (e.g., one hour).

d. The product price table is restricted to the director of marketing, who alone can approve changes to the price file.