What happens to river flow when its slope becomes gentle in plains?

Correct answer: Slow and winding

Direct answer: Option B is correct. River slope is the fall of the land along the river’s course. In the plains, the slope becomes gentle, meaning the height decreases only a little over a long distance. Gravity then provides less downhill component, so the river’s average velocity decreases. A slower river has more time to erode its banks sideways and deposit sediment, which encourages broad bends called meanders. Option A is wrong because a gentle slope generally does not make a river very fast or straight. Option C is wrong because reduced slope does not normally stop the river completely. Option D is wrong because river water does not naturally flow backward from the sea; it continues generally toward lower land and the sea. Option B therefore correctly combines slow movement with winding channels. Remember: steep slope usually means faster, straighter flow; gentle slope in plains usually means slower, wider, more meandering flow.