CDS (I) 2023 General Knowledge · Question 15 of 120

Correct — C, Assam. All three clues point the same way. 'Land of red river and blue hills' is Assam's standing nickname — the red river is the Brahmaputra, heavy with silt, and the blue hills are the ranges that frame the valley. The second clue is the strongest discriminator: Assam holds three of India's six great physiographic divisions at once, since the Himalayan and north-eastern hill country lies along its north and south-east, the Brahmaputra plain running through the middle belongs to the Northern Plains, and the Karbi Anglong and North Cachar hills in the south are a detached block of the Peninsular plateau. The third clue checks arithmetically: Assam's area is 78,438 square kilometres against India's 3,287,263, which is 2.39 per cent.

• (a)Karnataka — Karnataka is roughly two and a half times the size, at about 5.8 per cent of India, so the third clue alone rules it out. It also carries a different tourism tagline, and its physiography is essentially plateau and coastal plain.
• (b)Andhra Pradesh — Neither the nickname nor the area fits — Andhra Pradesh covers roughly 5 per cent of the country. Its landscape is plateau and a long eastern coastal plain, without any Himalayan or north-eastern hill component.
• (d)Chhattisgarh — Chhattisgarh is a landlocked plateau state of about 4.1 per cent of India's area, with no great silt-laden river of the Brahmaputra kind and no Himalayan segment at all.

India is conventionally divided into six physiographic units — the Northern and North-eastern Mountains, the Northern Plains, the Peninsular Plateau, the Indian Desert, the Coastal Plains and the Islands. Most states sit squarely inside one or two of them. Assam is unusual in containing three: the eastern Himalayan and Purvanchal hill country, the alluvial Brahmaputra plain, and the Karbi Anglong and North Cachar hills, which geologists read as an outlier of the peninsular block that drifted north-east. That combination in a single medium-sized state is what the second clue is pointing at.

Clue-based state identification is a recurring CDS format, and the technique is to find the clue that eliminates fastest rather than the one you recognise first. Here that is the area figure: 2.39 per cent of India is a little under 79,000 square kilometres, and only one option is anywhere near it. The nickname then confirms rather than carries the answer. It is worth noting what the nickname means, since 'red river' is often misread as a name — the Brahmaputra is called red for the load of silt it carries down from Tibet and the eastern Himalaya, which is also why its braided channel shifts so much and why Majuli, the great river island in its course, has been shrinking.

• Assam's area is 78,438 square kilometres, about 2.39 per cent of India's 3,287,263 square kilometres.
• Assam's nickname is the land of red river and blue hills — the Brahmaputra and the ranges around the valley.
• It contains three of India's six physiographic divisions: the north-eastern hills, the Brahmaputra plain, and the Karbi Anglong and North Cachar hills of peninsular origin.
• The Barak valley in southern Assam is the state's second river plain, draining towards Bangladesh.
• Majuli, in the Brahmaputra, is among the largest river islands in the world.

• Treating the nickname as the only usable clue and guessing when it is unfamiliar.
• Reading 'red river' as a proper name rather than a description of the Brahmaputra's silt.
• Assuming a north-eastern state must be small, and rejecting Assam on the area figure without checking it.

As a clue-based identification like this one, or as a direct item on which state contains a named physiographic feature.

• practice — not a real PYQ

  The Karbi Anglong and North Cachar hills of Assam are usually treated as an outlying part of which physiographic division of India?

  • (a)The Northern Plains
  • (b)The Peninsular Plateau
  • (c)The Coastal Plains
  • (d)The Indian Desert

  Answer(b) The Peninsular Plateau — these hills are read as a detached block of the peninsular shield, which is why Assam counts three physiographic divisions.

• practice — not a real PYQ

  Majuli, one of the largest river islands in the world, lies in which one of the following rivers?

  • (a)Ganga
  • (b)Godavari
  • (c)Brahmaputra
  • (d)Mahanadi

  Answer(c) Brahmaputra — Majuli lies in the Brahmaputra in Assam and has been losing area to the river's shifting channels.