Which of the following peaks is not situated in the Andaman and Nicobar region…

The Andaman and Nicobar Islands form a tectonic island-arc chain in the Bay of Bengal, shaped mainly by the convergence of tectonic plates. Present-day active volcanism is confined to a single island, Barren Island (India's only currently active volcano), while at least one other island, Narcondam, is volcanic in origin but now dormant. The archipelago is made up of the Andaman group in the north and the Nicobar group in the south. Several named hills and peaks lie within this archipelago (across North, Middle, and South Andaman), and these are distinct from any similarly named or unrelated peaks found on the Indian mainland.

To find the peak that is not situated in the Andaman and Nicobar region, each named option needs to be checked against its actual geographic location:

• Saddle Peak, at roughly 732 metres, lies within the North Andaman hill system inside Saddle Peak National Park.

• Mount Diavolo, at roughly 511 metres, forms part of the Middle Andaman range.

• Mahendragiri, at roughly 1,501 metres, rises in the Eastern Ghats of Gajapati district, Odisha, well inland on the Indian mainland, and was notified as a Biodiversity Heritage Site on 25 November 2022.

• Mount Koyob, at roughly 459 metres, is one of the peaks recorded within the Andaman archipelago's interior hill ranges.

This is corroborated by the RSSB Patwar 2025 Shift 2 official answer key, which marks Mahendragiri as the correct response for this question - consistent with Mahendragiri being situated in the Eastern Ghats of Odisha, outside the Andaman and Nicobar Islands, while Saddle Peak, Mount Diavolo, and Mount Koyob are all peaks within the archipelago itself.

Therefore, Mahendragiri is the peak that is not situated in the Andaman and Nicobar region of India.