Q150. Which is a tributary of the Brahmaputra?
[WBCS Mains (2021)]
(A) Subansiri
(B) Godavari
(C) Ganga
(D) Ghaghara
Answer: (A) Subansiri
Explanation: The Subansiri rises in the eastern Himalayas and enters the Brahmaputra in Assam. It is one of the major northern tributaries supplying water and sediment. Himalayan sediment, seasonal floodwater and heavy rainfall strongly shape the river channels and adjoining plains.
Q149. Which city is situated near the mouth of the Tapi River?
[WBCS Mains (2021)]
(A) Ankleshwar
(B) Ahmedabad
(C) Vadodara
(D) Surat
Answer: (D) Surat
Explanation: Surat lies on the Tapi in Gujarat, close to the river’s Arabian Sea estuary. The city’s riverfront is historically associated with trade and periodic floods. Rivers shaped settlement, local trade routes and agriculture throughout the adjoining plains and valleys.
Q148. At which place do the Bhagirathi and Alaknanda meet?
[WBCS Mains (2021)]
(A) Devprayag
(B) Rudraprayag
(C) Haridwar
(D) Karnaprayag
Answer: (A) Devprayag
Explanation: The two Himalayan headstreams unite at Devprayag in Uttarakhand; downstream their combined course is called the Ganga. Rudraprayag is the meeting place of the Alaknanda and Mandakini. Regional relief, river outlets and tributary connections help distinguish the surrounding drainage basin geographically.
Q147. The Indus is an example of which type of river?
[WBCS Mains (2021)]
(A) Consequent
(B) Antecedent
(C) Obsequent
(D) Subsequent
Answer: (B) Antecedent
Explanation: The Indus maintains its course across mountain uplift and cuts deep gorges through Himalayan terrain. Rivers whose courses predate the uplift are termed antecedent. Regional relief, river outlets and tributary connections help distinguish the surrounding drainage basin geographically.
Q146. Through which two states does the Beas flow?
[WBCS Mains (2021)]
(A) Rajasthan and Punjab
(B) Punjab and Himachal Pradesh
(C) Haryana and Uttar Pradesh
(D) Haryana and Rajasthan
Answer: (B) Punjab and Himachal Pradesh
Explanation: The Beas rises near Rohtang Pass in Himachal Pradesh and enters Punjab before meeting the Sutlej near Harike. It belongs to the Indus drainage system. Regional relief, river outlets and tributary connections help distinguish the surrounding drainage basin geographically.
Q145. Who advocated the National Water Grid or river-linking concept?
[WBCS Mains (2021)]
(A) K. L. Rao
(B) P. V. Narasimha Rao
(C) Atal Bihari Vajpayee
(D) Narendra Modi
Answer: (A) K. L. Rao
Explanation: Engineer and former minister K. L. Rao advanced an early national water-grid proposal. The idea concerned transfers of water between surplus and deficit basins, although later programmes developed different plans. Regional relief, river outlets and tributary connections help distinguish the surrounding drainage basin geographically.
Q144. Which lake is treated as the largest in this exam question?
[WBCS Mains (2021)]
(A) Loktak
(B) Wular
(C) Vembanad
(D) Chilika
Answer: (B) Wular
Explanation: The exam key names Wular, a large freshwater lake in Kashmir. Lake comparisons depend on whether freshwater, brackish water, total area or seasonal fluctuations are being considered. The balance of rainfall, inflowing streams, evaporation and coastal connections determines the waterbody’s character.
Q143. Which of these rivers rise in the Eastern Ghats?
1. Brahmani;
2. Nagavali;
3. Subarnarekha;
4. Vamsadhara.
[UPSC CSE Prelims (2021)]
(A) 1 and 2 only
(B) 2 and 4 only
(C) 3 and 4 only
(D) 1 and 3 only
Answer: (B) 2 and 4 only
Explanation: Nagavali and Vamsadhara originate in the Eastern Ghats uplands. The Brahmani and Subarnarekha trace their origins farther inland in the Chota Nagpur region. Regional relief, river outlets and tributary connections help distinguish the surrounding drainage basin geographically.
Q142. In the Indus river system, which river receives the other three through tributary connections before its waters meet the Indus?
[UPSC CSE Prelims (2021)]
(A) Chenab
(B) Jhelum
(C) Ravi
(D) Sutlej
Answer: (D) Sutlej
Explanation: The exam treats Sutlej as the downstream receiving river in this group. Punjab rivers interconnect before the Panjnad ultimately joins the Indus in Pakistan. Regional relief, river outlets and tributary connections help distinguish the surrounding drainage basin geographically.
Q141. Which is not a tributary of the Brahmaputra?
[NDA-I General Ability Test (18 April 2021)]
(A) Manas
(B) Kameng
(C) Mahananda
(D) Subansiri
Answer: (C) Mahananda
Explanation: Mahananda rises near the Darjeeling hills and joins the Ganga basin. Manas, Kameng and Subansiri are important tributaries of the Brahmaputra. Himalayan sediment, seasonal floodwater and heavy rainfall strongly shape the river channels and adjoining plains.
