Correct Response: D. In contour plowing, the soil is tilled following the contours of hills rather than down the slope. This reduces the amount of soil that is washed away during rain and also increases the amount of water the soil can absorb. Contour plowing by itself does not increase organic matter (A); it just prevents it from being washed away. Contour plowing is a method of cultivation (B), or preparing the soil for planting, so it does not reduce the need to cultivate. Following the existing contours of the land when plowing does not change the angle at which light would hit the crops (C).
