The correct answer is (d). The National Renewal Fund (NRF) was constituted in 1987 to provide financial assistance to sick and potentially viable public sector undertakings (PSUs) for their restructuring and modernization. The NRF is a non-lapsable fund, which means that it does not lapse at the end of the financial year. The NRF is managed by the Ministry of Finance, and its operations are overseen by a board of directors. The NRF has been instrumental in helping to restructure and modernize a number of PSUs, including Air India, Indian Airlines, and Steel Authority of India Limited.
The other options are incorrect. Option (a) is incorrect because the NRF does not provide pension for retiring employees. Option (b) is incorrect because the NRF is not a social security fund. Option (c) is incorrect because the NRF is not a rural reconstruction fund.