Emile’s family is setting up a compost bin in their backyard in which organisms such as bacteria and earthworms will naturally recycle yard wastes and some foods. these organisms need both carbon and nitrogen to survive. which of these materials in the compost bin is most likely a good source of nitrogen?

Compost is formed by microorganisms that use organic materials as their food. Microorganisms needs four essential things in order to create a rich organic compost. These are carbon, nitrogen, oxygen and moisture. Materials that are rich in nitrogen are called "greens" in your compost. Examples are coffee grounds and grass clippings.