Control: On a monthly basis, the manager of corporate accounting reviews and approves the reconciliations for the corporate bank accounts. Unreconciled balances in excess of US$50,000 are investigated and resolved prior to close. Deficiency: During our test of control performed over a sample of 2 months (testing 20 reconciliations in each month), we detected control deficiencies in 5 reconciliations consisting of unreconciled balances in excess of US$50,000 that were not investigated and resolved in a timely manner. For this conrol deficiency, which is the appropriate type of deficiency to be selected from the options provided in the SOCD form? Operation Design and operation Not a deficiency Design