Final answer:
The OPC number or CVS submission code appears on the receipt, not on the invoice, prescription, or packaging.
Step-by-step explanation:
The OPC number or CVS Submission Code typically appears on the receipt after a customer completes a purchase at CVS Pharmacy. This code can be used by the pharmacy to track or reference a specific transaction. It is not found on the invoice, prescription, or packaging of the products, as these documents serve different purposes. An invoice is a request for payment, a prescription is a doctor's authorization for medication, and the packaging is the material that encases the product.