Which change is most expected when slope decreases in the plain course of Himalayan rivers?

Correct answer: Carrying capacity decreases and deposition increases

Direct answer: Option A is correct. A river’s carrying capacity is its ability to transport sediment such as sand, silt, and stones. In the steep Himalayan course, gravity gives water greater speed and energy. When the river enters the plains, the slope becomes gentler. Its speed and transporting power usually decrease, so the river cannot carry as much material. The extra sediment is deposited on the bed, banks, or floodplain. Option A correctly connects lower slope with lower carrying capacity and greater deposition. Option B is wrong because a lower slope does not make a river flow uphill; water still flows downhill. Option C is wrong because river water does not suddenly turn into sea salt. Option D is wrong because a river’s source does not change into a desert merely because the river enters the plains. The important chain is: gentle slope → lower velocity → lower carrying power → deposition. Exam cue: deposition is commonly associated with slowing water.