Concept:A public sector undertaking is a government-owned/controlled commercial enterprise.Explanation:LIC of India is established by an Act of Parliament and is owned/controlled by the Government of India, so it is a public sector undertaking. Indian Railways is a departmental undertaking, while Air India has been privatised to the Tata Group since 2022. Therefore, the clear public sector undertaking among the given options is LIC.Answer:A. LIC of India