Biodiversity hotspots of India

Known forThe eastern Himalaya’s compressed altitude range

The whole Himalayan arc from Kashmir to Arunachal, plus Nepal and Bhutan — but the endemism is concentrated in the wet eastern half, where the monsoon reaches the mountains and the altitude range compresses tropical forest and alpine meadow into forty kilometres. Deforestation on the lower slopes is what pushed the region past the seventy per cent loss the designation requires.

SettingHimalayan arc · tropical to alpine in 40 km · rhododendron and oak · snow leopard and red panda

For the examThe hotspot is the whole arc, but the qualifying endemism is eastern — that distinction is what the question tests.

Known forThe north-east, and the Andamans with it

The largest of the four in extent, running from north-east India through Myanmar into Indochina — and India’s share is the Purvanchal hills, the Brahmaputra valley and the Andaman islands. It is the hotspot with the highest rate of new species descriptions anywhere, because it is the least surveyed.

SettingPurvanchal hills and Brahmaputra valley · tropical evergreen · hoolock gibbon · new species still being described

For the examThe Andaman islands belong to this hotspot; the Nicobars belong to Sundaland. Papers swap them.

Known forIndia’s Nicobar doorway into a South-East Asian hotspot

A hotspot of Indonesia, Malaysia and Brunei that reaches India through one doorway: the Nicobar islands sit on the Sunda shelf and carry Sundaland’s flora and fauna, not the subcontinent’s. Everything about India’s share is small, endemic and easy to lose — the Nicobar megapode and the Nicobar treeshrew live nowhere else.

SettingSunda shelf islands · tropical evergreen · Nicobar megapode · island endemism

For the examIndia’s share of Sundaland is the Nicobars only. The Andamans are Indo-Burma, which is the trap.

Known forThe Ghats wall, with Sri Lanka in the same hotspot

A sixteen-hundred-kilometre wall of hills and the island beyond it, treated as one hotspot because they were one landmass and share their lineages. Its endemism is what a barrier produces — the Palghat gap alone separates species either side of it — and its vegetation loss is what two centuries of plantation and reservoir did.

SettingWestern Ghats and Sri Lanka · shola–grassland · lion-tailed macaque · Palghat gap barrier

For the examIt is not "the Western Ghats" alone — Sri Lanka is in the same hotspot, and the pairing is the answer.