Which of the Following Statements Is Correct Regarding Accounts Payable

Which of the following statements is correct regarding accounts payable and the auditor's procedures?

A) Because it can be difficult to discover a transaction that has not been recorded,the audit objective of completeness drives many of the substantive procedures applied to these balances.
B) A judgment whether an unrecorded payable should be recorded before the financial statements are prepared depends entirely upon the source of the payable.
C) The confirmation of accounts payable selected from the year-end trial balance of such accounts is most effective in discovering unrecorded liabilities.
D) Unrecorded payables are often discovered through examining vouchers payable entered into the voucher register prior to the balance sheet date.