In a practice known as crop rotation, farmers alternate a crop of legumes (plants whose roots bear nodules containing Rhizobium) with a crop of nonlegumes. What is the benefit of this practice?
a. It keeps those bacteria that are plant pathogens from becoming pesticide resistant.
b. Rhizobium fixes nitrogen, and the fixed nitrogen will fertilize the soil.
c. It prevents the farmer from being exposed to the same crop pathogens year after year.
d. It keeps the plants from becoming pesticide resistant.
e. It keeps the plants from becoming tolerant of the bacteria in a particular variety of soil.