The correct option is D The unstable nature of the Ghaggar river
The Brahmaputra river causes devastating floods in Assam and Bangladesh as well during the rainy season. When the Brahmaputra river enters India, it passes through the region of high rainfall. Hence, it carries a large volume of water and a considerable amount of silt here. The embankments are filled with sediment, reducing the water-carrying capacity of the river resulting in floods.