Return scrutiny enables tax officers to seek explanations for discrepancies and initiate assessment or enforcement if explanations are unsatisfactory. Scrutiny of returns allows the proper officer to verify correctness of returns and related particulars, inform the taxable person of discrepancies and seek explanations; acceptable explanations preclude further action, while unsatisfactory or unaddressed explanations or failure to correct accepted discrepancies permit the officer to initiate appropriate action or determine tax and other dues under the specified subsections.