Answer :
Answer: C. Nitrogen cycling is the process by which nitrogen from the atmosphere and decomposed organic materials are converted by soil bacteria to compounds that can be assimilated by plants.
Explanation:
The nitrogen cycling is a community level property. Also the decomposition of organic material is also a community effort.
The nitrogen cycling is performed by the soil microbes which convert the atmospheric nitrogen into forms used by the plants. The plants provide nourishment to herbivores and omnivores. This way nitrogen is cycled within different organisms and the spheres of earth.
The soil bacteria decompose the organic materials making the nutrients available to the plants.