In Terrain with Steep Hill Slopes, Which Crop and Cultivation

Multiple Choice

In terrain with steep hill slopes, which crop and cultivation technique will minimize soil erosion?

A) apples; land between the trees is planted in grass and not cultivated
B) bean; rows are spaced wider than on a level field
C) winter wheat; after the harvest, the field is plowed and left idle until next fall
D) corn; rows trending straight down the slope, frequent cultivation