Answer:
A. decomposition
Step-by-step explanation:
Decomposers are microorganisms such as bacteria, fungi and worms. These organisms are significant decomposers which can break down most types of organic matter. All the living organisms are made of carbon. They all require carbon their growth and reproduction. Decomposers decompose dead organisms and use the carbon dioxide released from them for their food. Therefore, decomposers help in cycling of carbon from dead bodies into the atmosphere through cellular respiration.