Consider the following statements: 1. NTPD is the largest power utility in India. 2. ONGC accounts for half of the LPG production in India. 3. Indian Oil Corporation operates all the oil refineries in India. 4. The Indian Ordinance Factory is the largest departmentally run industrial undertaking in the country. Which of these statements is/are correct?

1. Statement 1 appears correct. NTPC Limited (National Thermal Power Corporation) is India's largest power generation company (utility). 2. Statement 2 is incorrect. ONGC (Oil and Natural Gas Corporation) is primarily involved in exploration and production of crude oil and natural gas. While it produces some LPG (Liquefied Petroleum Gas) as a byproduct, the majority of LPG production and supply in India comes from oil refineries (run by IOCL, BPCL, HPCL) processing crude oil and from imports. ONGC does not account for half the LPG production. 3. Statement 3 is incorrect. Indian Oil Corporation (IOC) is the largest oil refining and marketing company in India, but it does not operate *all* the oil refineries. Other public sector companies like BPCL, HPCL, and private players like Reliance Industries also operate major refineries. 4. Statement 4 is correct. The Indian Ordnance Factories organization, under the Ministry of Defence, comprising numerous factories producing defence equipment and arms, was considered the largest departmentally run industrial undertaking in the country (before its recent corporatization). 5. Therefore, statements 1 and 4 are correct.