Legumes Are Frequently Grown in Rotation with Primary Field Crops

Multiple Choice

Legumes are frequently grown in rotation with primary field crops. What is the benefit of this practice?

A) A greater amount of the primary crop can be harvested each year.
B) Nitrogen is added to the soil because of the legumes' symbiotic nitrogen-fixing bacteria.
C) Soil erosion is reduced by frequent plowing.
D) Legumes decrease the amount of organic material in the soil.