Indian Geography

The longitudinal divisions of the Himalayas from west to east are demarcated by river valleys. The part lying between the Indus and Satluj rivers is traditionally known as the Punjab Himalayas (also regionally referred to as Kashmir and Himachal Himalayas).

All three statements are correct. The Himalayas are not a straight line; they curve sharply southward at both ends. This is due to the syntaxial bends (or knee-bend turns) caused by the tectonic push of the Indian Plate against the Eurasian Plate. The western syntaxial bend lies near Nanga Parbat (Pakistan-administered Kashmir) where the Indus River flows. The eastern syntaxial bend lies near Namcha Barwa in Tibet/Arunachal border where the Brahmaputra River bends sharply to enter India.

All pairs are correctly matched. According to the regional classification of the Himalayas by Sir Sidney Burrard: Punjab Himalayas lie between Indus and Satluj; Kumaon Himalayas lie between Satluj and Kali; Nepal Himalayas lie between Kali and Teesta; and Assam Himalayas lie between Teesta and Dihang (Brahmaputra).

All three statements are correct. The Himalayas exhibit syntaxial (hairpin) bends at both their western (around Nanga Parbat, where the Indus River cuts a deep gorge) and eastern (around Namcha Barwa, where the Tsangpo/Brahmaputra River cuts a deep gorge and enters India) extremities, causing the ranges to sweep sharply southwards.

Nathu La is a mountain pass in the Himalayas that connects the Indian state of Sikkim with China's Tibet Autonomous Region. It was reopened in 2006 for border trade.

The correct longitudinal sequence from West to East is: Zoji La (located in Ladakh/Jammu & Kashmir) -> Shipki La (Himachal Pradesh, near the India-China border) -> Jelep La (Sikkim, passing through the Chumbi Valley) -> Bomdi La (Arunachal Pradesh). Hence, the correct order is 3-1-2-4.

The Shiwaliks (or Outer Himalayas) are the southernmost and the youngest range of the Himalayan mountain system. They are composed of unconsolidated sediments brought down by rivers from the main Himalayan ranges located farther north.

The Great or Inner Himalayas are also known as the 'Himadri'. It is the most continuous, loftiest northernmost range of the Himalayas, containing most of the world's highest peaks, with an average height of about 6,000 metres.

Both statements are correct. The longitudinal valleys between the Lesser Himalayas and the Shiwaliks are called Duns (e.g., Dehradun, Patli Dun) in the west and Duars in the east. Additionally, the southern slopes of the Shiwaliks in Punjab and Himachal Pradesh are heavily dissected by seasonal torrential streams called 'Chos', which cause severe soil erosion.

All three statements are correct. Karewas are lacustrine (lake) deposits of glacial clay and other materials embedded with moraines, characteristic of the Kashmir valley. They are famous for the cultivation of Zafran, a local variety of saffron. Dal and Wular are prominent freshwater lakes located in this Himalayan segment, while salt water lakes like Pangong Tso and Tso Moriri lie further east in the Ladakh region.