Q70. Which of these Himalayan rivers is not generally classified as antecedent?
[WBCS Mains (2016)]
(A) Indus
(B) Sutlej
(C) Kali
(D) Brahmaputra
Answer: (C) Kali
Explanation: The Indus, Sutlej and Brahmaputra are classic trans-Himalayan antecedent rivers. Kali, in the provided classification, is not treated as an antecedent trunk stream. Regional relief, river outlets and tributary connections help distinguish the surrounding drainage basin geographically.
Q69. Which of the following is not a Ganga tributary?
[WBCS Mains (2016)]
(A) Gandak
(B) Gomti
(C) Kosi
(D) Ghaggar
Answer: (D) Ghaggar
Explanation: The Ghaggar is an intermittent river draining northwest India and dissipating in arid plains. Gandak, Gomti and Kosi are all part of the Ganga catchment. The wider drainage network links Himalayan tributaries with major alluvial floodplains and downstream deltas.
Q68. Which is the largest brackish-water lake among these?
[WBCS Mains (2016)]
(A) Lonar
(B) Pulicat
(C) Chilika
(D) Wular
Answer: (C) Chilika
Explanation: Chilika is the large brackish lagoon along the Odisha coast. Wular is freshwater, while Lonar occupies a meteor-impact crater in basalt. The balance of rainfall, inflowing streams, evaporation and coastal connections determines the waterbody’s character.
Q67. Which dam–river match is wrong?
[WBCS Mains (2016)]
(A) Nagarjuna Sagar–Krishna
(B) Hirakud–Mahanadi
(C) Bhakra–Sutlej
(D) Ukai–Chambal
Answer: (D) Ukai–Chambal
Explanation: Ukai Dam is constructed across the Tapi in Gujarat, not across the Chambal. The other project–river combinations are correct. Reservoir location, river discharge and terrain affect the supply of water for irrigation and electricity.
Q66. Through which countries or regions does the Brahmaputra flow?
[WBCS Mains (2016)]
(A) Tibet, India and Bangladesh
(B) India, Pakistan and Bangladesh
(C) Bhutan, Nepal and India
(D) Sri Lanka, India and Bangladesh
Answer: (A) Tibet, India and Bangladesh
Explanation: The river starts as Yarlung Tsangpo in Tibet, crosses Arunachal Pradesh and Assam in India, and continues into Bangladesh as Jamuna. Himalayan sediment, seasonal floodwater and heavy rainfall strongly shape the river channels and adjoining plains.
Q65. Which is the highest dam in India among the options?
[WBCS Mains (2016)]
(A) Tehri
(B) Bhakra Nangal
(C) Hirakud
(D) Nagarjuna Sagar
Answer: (A) Tehri
Explanation: The Tehri earth-and-rockfill dam rises high above the Bhagirathi in Uttarakhand. Its reservoir regulates Himalayan runoff for hydroelectricity and water supply. Reservoir location, river discharge and terrain affect the supply of water for irrigation and electricity.
Q64. Marble Falls is associated with which river?
[WBCS Mains (2016)]
(A) Cauvery
(B) Sharavati
(C) Narmada
(D) Godavari
Answer: (C) Narmada
Explanation: The famous Marble Rocks gorge and the nearby Dhuandhar cascade are located on the Narmada at Bhedaghat near Jabalpur in Madhya Pradesh. Waterfalls develop where river gradients shift abruptly, often across resistant rock or geological breaks.
Q63. Which two rivers form the principal Ganga headstreams?
[WBCS Mains (2016)]
(A) Bhagirathi and Yamuna
(B) Bhagirathi and Alaknanda
(C) Mandakini and Yamuna
(D) Mandakini and Son
Answer: (B) Bhagirathi and Alaknanda
Explanation: The Bhagirathi and Alaknanda unite at Devprayag to form the named Ganga. The Yamuna is a separate major tributary meeting it later at Prayagraj. The wider drainage network links Himalayan tributaries with major alluvial floodplains and downstream deltas.
Q62. Which major river-linking pair had recently been connected through a diversion project?
[UPSC CSE Prelims (2016)]
(A) Cauvery and Tungabhadra
(B) Godavari and Krishna
(C) Mahanadi and Son
(D) Narmada and Tapi
Answer: (B) Godavari and Krishna
Explanation: The Pattiseema lift irrigation project transfers Godavari water to the Krishna basin in Andhra Pradesh. The relevant river linkage was operationalised in 2015. Regional relief, river outlets and tributary connections help distinguish the surrounding drainage basin geographically.
Q61. Place Brahmaputra tributaries Lohit, Teesta, Subansiri and Sankosh from west to east.
[CDS-I General Knowledge (14 February 2016)]
(A) Teesta, Sankosh, Subansiri, Lohit
(B) Teesta, Subansiri, Sankosh, Lohit
(C) Sankosh, Teesta, Subansiri, Lohit
(D) Subansiri, Lohit, Teesta, Sankosh
Answer: (A) Teesta, Sankosh, Subansiri, Lohit
Explanation: Teesta and Sankosh join in the western part of the Brahmaputra system, while Subansiri and Lohit lie successively farther east. Thus the first sequence is correct. Himalayan sediment, seasonal floodwater and heavy rainfall strongly shape the river channels and adjoining plains.
