Answer:
D. forest
Step-by-step explanation:
Forests play a vital role in soil health and water quality. Not only do they act as anchors for the loose soil, they are also living filtering mechanisms. Without trees, during heavy rainfall, the amount of water will exceed the soil's capacity to absorb it. Thus, this excess will run off collecting not only soil particles (which leads to soil erosion), but also chemicals and pollutants. All this will end up in streams and rivers and thus affect aquatic ecosystems and water quality. These water sources will in turn cause floods that can inflict heavy damages.
A forest canopy will limit the amount of water that reaches the soil. Furthermore, large amounts of water are absorbed by trees on a daily basis. With this water, any pollutants or excess nutrients due to human activity are absorbed and stored inside the trees. Thus, trees play a vital role for the natural circulation and filtration of water.