Which is NOT a duty of the bank to the customer?

The duty of a bank to its customer involves several responsibilities that align with normal banking practices and customer service. Charging interest on all deposits is not necessarily a requirement or duty of the bank. While banks may charge interest on certain types of accounts—such as loans or credit agreements—there are also many types of deposit accounts that typically do not attract interest, such as current accounts.

Furthermore, the bank's duty is not uniform across all accounts; it often depends on the type of account and the terms of the agreement made with the customer. Banks do offer interest on savings accounts, but they are not obliged to charge interest on all deposits, which makes this option the correct choice in this context.

In contrast, crediting cash/payment orders, respecting confidentiality, and highlighting attempts to forge signatures are all fundamental responsibilities of banks towards their customers. These actions help maintain customer trust and financial security, which are paramount in the banking relationship.