Control: On a monthly basis, the financial analyst performs the reconciliation of the AR subledger system to the general ledger. All reconciling items in excess of US$15,000 are investigated and resolved. Deficiency: During our test of control of a sample of 2 months, March and September, from the first nine months of the audit period, we identified unexplained reconciling items in excess of US$15,000 in the reconciliations for the two months selected for testing. This an integrated audit of a publicly held client. Which of the following actions is appropriate to be part of our response to this deficiency? Select the correct option and select Submit. Reduce our substantive procedures for AR Modify our control risk assessment from "not rely" to "rely" Test reconciliations once management has remediated the control Extend our sample size for control testing from the first nine months of the audit period