Answer: C. On a sloped parking lot
Surface runoff can be referred as the flow of water, that occurs when the excess water flows from the storm water, melt water, flood, rain streams and rain fall. The fast moving water current takes along with it superficial layers like surface and sub- surface layers of soil. Hence, causes water erosion of soil.
The slope parking lot will favor, surface runoff more likely than in a grassy prairie, mulched flower bed, or in a sand pit because the slope will provide a surface for free flow of water. There are chances that water gets absorbed by the soil in the grassy prairie, mulched flower bed and sand pit. Whereas the slopy surface of parking lot will not allow the water retention by soil, instead will accelerate the flow of water.