The two volcanic Islands in the Indian Territory are -

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Correct — D, Narcondam and Barren. Both lie in the Andaman group in the Bay of Bengal, and both are volcanic for the same reason: the Indian Plate is being subducted beneath the Burma plate, and the melt generated along that subduction zone has built a chain of volcanoes running from Sumatra through the Andamans to Myanmar. Barren Island is the only confirmed active volcano in the Indian subcontinent, and the only active one along that entire Sumatra-to-Myanmar chain. It is an uninhabited cone of 8.34 sq km rising to 353–354 m, about 138 km north-east of Port Blair. Its recorded history opens with an eruption in 1787 and continues through 1789, 1795, 1803–04 and 1852; then came nearly a century and a half of dormancy, broken by a six-month eruption in 1991 that caused considerable damage. It has been restless ever since — lava fountains confirmed in January 2017, activity through 2019, and from 2022 an almost constant state of eruption, with a further eruption recorded on 22 September 2025, nine days after this paper was written. Narcondam is the quieter twin: 7.6 sq km, rising to 710 m, 256 km north-east of Port Blair. Textbooks generally describe it as dormant, and it was not known to have been active in recent times until reports of mud and smoke on 8 June 2005 — but the Geological Survey of India classifies it as an active volcano, so it should never be called extinct. Apart from a small police detachment it is uninhabited, it is notified as the Narcondam Island Wildlife Sanctuary, and it is the sole home of the endemic Narcondam hornbill (Rhyticeros narcondami), a threatened bird numbering between 300 and 650 individuals.

Why the other options are wrong — (a) Two islands that could hardly be less volcanic. Kavaratti is a coral atoll and the capital of Lakshadweep — 4.22 sq km with a 4.96 sq km lagoon, about 360 km west of the Malabar coast. New Moore, also called South Talpatti or Purbasha, was a low silt bar that surfaced in the Bay of Bengal after the Bhola cyclone of November 1970, was claimed by both India and Bangladesh, and went under water around March 2010.  (b) Both are Lakshadweep coral atolls. Bitra, in the Aminidivi group, is a 0.187 sq km atoll with a lagoon and the smallest of Lakshadweep's populated islands (271 people in the 2011 Census). Picking this means reading 'island in Indian territory' as 'Indian island I have heard of' — Lakshadweep is a reef-built archipelago with no volcanism at all.  (c) The designed near-miss, because half of it is right. Barren belongs; Pamban does not. Pamban is the 96.6 sq km island carrying Rameswaram in Ramanathapuram district, Tamil Nadu, about 2 km off the mainland and separated from Sri Lanka's Mannar Island by the Palk Strait — a low, sandy, coral-fringed island reached by the Pamban bridge opened on 24 February 1914.

Concept: Islands in Indian waters come from three quite different processes, and the question is really asking you to sort by process rather than by name. The first is volcanic: the Andaman and Nicobar chain is the emergent crest of a submarine ridge thrown up where the Indian Plate dives beneath the Burma plate, an arc that continues north into the Arakan Yoma of Myanmar and south to Sumatra. Barren and Narcondam stand slightly east of the main chain as separate volcanic cones on that arc. The second is biogenic: the Lakshadweep islands are coral atolls, built up by reef organisms on the crest of a submerged ridge, with a lagoon enclosed by a reef rim and no volcanic activity. The third is continental or depositional: Pamban is a low fragment of the continental shelf off the Tamil Nadu coast, and New Moore was simply an accumulation of silt. The governing principle is that a volcano needs a magma source, which in practice means an active plate boundary — and India's only one inside its own waters is the Andaman arc.

State PCS 2025 Q109 — Geography PYQ with Answer

State PCS 2025 Q109 — Geography PYQ with Answer