Correct answer: C). Levees prevent rivers from adding their sediment to wetlands.
Wetlands are that part of the natural environment, that protect the shores from the wave action, absorbs pollutants, improve the water quality and reduce the impact of the flood.
They also provide habitat for animals and plants. The natural levees are formed by the natural movement of water that pushes the sediment to the site and form levees. The levees are made of slit, sand sediment and other mater pushed by the water flow to the side of the river.
