Which of the following duns lies to the west of the Dehra Dun valley?

Correct answer: (c) Pijori Dun

Explanation

Duns are long, flat-floored valleys between the Shivalik and the Lesser Himalaya, filled with sediment. Dehra Dun (Uttarakhand), between the Ganga and the Yamuna, is the best known.

• Pinjore Dun ("Pijori Dun"), near Chandigarh, in the Shivalik of Haryana and Himachal Pradesh, lies west of Dehra Dun.
• Patli Dun is the valley of the Ramganga in the Corbett National Park (Uttarakhand), east of Dehra Dun.
• Kotli Dun is another well-known dun of the Shivalik belt.

The book's key is (a), Patli Dun. But Patli Dun, in the Corbett National Park, lies east of Dehra Dun; Pinjore (Pijori) Dun, near Chandigarh, lies to its west, so (c) is the answer.