The correct option is (c) 1 and 3 only.
Explanation
The Brahmaputra river system exhibits distinct characteristics in its different stretches. While its upper course in Tibet passes through a cold and dry region, its nature changes drastically upon entering India due to climatic and topographical variations.Statement-wise Analysis:
- Statement 1 is Correct: Upon entering India, the Brahmaputra passes through Arunachal Pradesh and Assam. This region receives very high rainfall, particularly during the monsoon season.
- Statement 2 is Incorrect: In Tibet, the river carries a smaller volume of water and less silt because it is a cold and dry area. However, in India, it passes through a region of high rainfall. Here, the river carries a large volume of water and a considerable amount of silt.
- Statement 3 is Correct: Due to the heavy load of silt carried from the upper reaches and the tributaries in the high-rainfall region, the river deposits huge quantities of silt on its bed. This sedimentation causes the riverbed to rise, leading to frequent shifting of river channels and the formation of braided channels (e.g., Majuli Island).
Key Takeaway: The Brahmaputra in India is characterized by a high volume of water and heavy silt deposition, unlike its course in Tibet where it carries less water and silt.