Final answer:
An invoice is a true statement that serves as a notification to a customer to make a payment for shipped merchandise, resembling the immediate money transfer function of a debit card.
Step-by-step explanation:
True, an invoice is indeed a business document that may be provided in paper form or as an electronic transmission. Its primary purpose is to notify the customer of their obligation to pay the seller for merchandise that was ordered and subsequently shipped. This transaction is analogous to using a debit card, which serves as an instruction to the user's bank to transfer money directly and immediately from the customer's bank account to the seller.