Soybeans, Which Are a Type of Legume, Are Often Planted

Soybeans, which are a type of legume, are often planted in fields in which corn had been grown the year before. Why?

A) Soybeans carry out C₃ photosynthesis and corn carries out C₄ photosynthesis.
B) Soybeans need less light.
C) Soybeans add reduced nitrogen to the soil.
D) Soybeans produce seeds rich in oils.
E) Soybeans can produce reduced sulfur compounds.