A Valley Bottom Might Be Differentiated from Valley Sides in That________

A valley bottom might be differentiated from valley sides in that________ .

A) valley bottoms are the sites of interfluves
B) valley sides tend to take more area than valley bottoms
C) valley sides commonly have "lips" or "rims"
D) valley bottoms tend to be at a higher altitude
E) valley sides have lesser slopes than valley bottoms