Which of the following is most likely to be detected by an auditor review of a client cutoff

cooper, cpa, is auditing the financial statements of a small rural municipality. the recievable balances represent residences delinquent real esate taxes. Internal control at the municipality is weak. To determine the exsistence of the accounts receivable at the balance sheet date, Cooper would most likely: 1. send postive confirmation requests 2. send negative confirmtion request 3. examine evidence of subsequent cash receipts

4. inspect the internal records, such as copies of the tax invoices that were mailed to the residents