Detailed Explanation:

Answer: Option 4 — 1 only

Only Statement 1 is correct. Barren Island is indeed India's only active volcano, located in the Andaman Sea within Indian territory. Statement 2 is incorrect because Barren Island lies approximately 135-140 km east of Port Blair, not Great Nicobar, which is much further south. Statement 3 is also incorrect as the volcano has erupted multiple times after 1991, including in 1994-95, 2005-07, and most recently in 2017, proving it has not remained inactive.

✅ Statement 1 – Correct: Barren Island is the only confirmed active volcano in India, located in the Andaman Sea, part of the Union Territory of Andaman and Nicobar Islands.
❌ Statement 2 – Incorrect: Barren Island is located approximately 135-140 km east of Port Blair, not Great Nicobar; Great Nicobar is the southernmost island located much further south (around 7°N) while Barren Island is at approximately 12.2°N.
❌ Statement 3 – Incorrect: The volcano has not remained inactive since 1991; it has erupted several times including in 1994-95, 2005-07, and as recently as 2017.

📝 Short Notes: Barren Island Volcano

• Location: Barren Island is located in the Andaman Sea, approximately 135-140 km east of Port Blair in the Andaman and Nicobar Islands.
• Only Active Volcano: It is the only confirmed active volcano in South Asia and India.
• Part of Volcanic Arc: Barren Island is part of the volcanic arc chain extending from Sumatra to Myanmar, formed due to the subduction of the Indian Plate beneath the Burmese Plate.
• Eruption History: After lying dormant for nearly 150 years, it erupted in 1991, and has since shown activity in 1994-95, 2005-07, and 2017.
• Uninhabited: The island is uninhabited due to volcanic activity and is restricted for tourism, though diving expeditions are sometimes permitted.
• Geographical Coordinates: Approximately 12.2°N latitude and 93.9°E longitude.