Concept:A pay-in-slip is the standard bank form used when depositing cash into a bank account.Explanation:When cash is paid into a bank account, the customer fills a pay-in-slip with details such as the date, account number, and amount.The bank stamps one copy as proof of deposit, making it the main source document for recording the transaction.Invoices and credit notes relate to sales or returns, while a cheque book is used for making payments, not depositing cash.Answer:D. pay-in-slip