Indicate the primary audit objective for the following audit procedure: Add the accounts receivable aged trial balance and agree the total with the master file and general ledger. Occurrence O Completeness - transactions Accuracy - transactions O Classification - transactions O Timing O Posting and summarization O Existence O Completeness - balances O Accuracy balances O Classification - balances O Detail tie-in Completeness - balances O Accuracy - balances O Classification - balances Detail tie-in Realizable value