30 POINTS
Rhizobium is a bacteria that invades the root nodules of certain plants. These bacteria obtain nutrients from the plant cells and also fix atmospheric nitrogen so it can be used by the plants. Which statement describes the relationship between the two organisms?
A. The bacteria don’t harm the plants but benefit only themselves.
B. The plants harm the bacteria but benefit themselves.
C. The relationship benefits both the plants and the bacteria.
D. The association harms both the bacteria and the plants.
