Final answer:
The bank customer is obligated to report unauthorized signatures within a reasonable time to potentially recover the lost funds from the bank.
Step-by-step explanation:
The correct answer with respect to a bank customer's duty to discover and report unauthorized signatures is B) The customer must report unauthorized signatures within a reasonable time. This obligation is generally detailed in the agreement between the bank and the customer, and stems from laws that govern bank accounts and fraud, such as the Uniform Commercial Code (UCC) in the United States. Banks typically provide periodic account statements to customers, and the customers are expected to review these statements to identify any discrepancies or unauthorized transactions. If a customer fails to report an unauthorized signature within the stipulated time frame, which can vary depending on the jurisdiction and the specifics of the bank account agreement, they might lose the ability to recover the lost funds from the bank. By reporting unauthorized signatures promptly, customers can protect themselves from any potential fraudulent activity and help the bank investigate and resolve the issue.