If the taxpayer does not file the income tax return in response to the inquiry notice, such cases will be investigated. This notice is issued under section 142(1) when the taxpayer has not filed the tax return or additional preliminary information in respect of any particular detail such as bank interest or long-term capital gain on sale of asset-loss on sale. This guidance is part of the comprehensive guidelines recently issued by the Central Board of Direct Taxes (CBDT), which mention the mandatory option for deeper verification of income tax returns. These guidelines are issued annually. Which relates to the selection and thorough investigation to be conducted during the current financial year and survey of cases, search and seizure cases, tax evasion cases, cases in which notice under section 142(1) has been issued but no I.T. Returns have not been given. Has been filed. It also includes matters related to de-registration or cancellation of registration under various sections, such as registration of charitable organizations under 12A-12AB to be eligible for tax benefits. Further if there is increase in the income of the taxpayers in the previous year on any recurring issue, the IT return will be taken under mandatory verification guidelines, subject to the prescribed financial limit. The guidelines also prescribe the roles and responsibilities of IT officials and the National Faceless Assessment Centre.