The Degree of Erosion in the United States Is Best

The degree of erosion in the United States is best described by the following statement.

A) There is a set amount of soil that was originally formed and erosion continually removes some of it; therefore we will one day run out of topsoil due to erosion.
B) Soil forms at generally the same rate as soil erodes, so there is an overall balance just as worldwide precipitation equals evaporation; it is just not evenly spread across the landscape.
C) Soil is eroding faster than it is being formed on about one-third of all cropland.
D) Removal of trees helps build up topsoil and prevents erosion.