The model shows the cycling of carbon Carbon dioxide
in air
Green plants
absorb CO2
Animals
respiration
Decomposers
respiration
Food for
animals
Death
Waste materials
Which part of the model shows carbon moving from the biosphere to the
atmosphere?

A. Decomposers breaking down the material

Explanation:

Decomposition is the process in which decomposers such as bacteria break down the organic material in the atmosphere.

In the given image, decomposers breaking down the material shows carbon moving from the biosphere to the  atmosphere because decomposers break down the dead organisms and in the process the carbon in the bodies of dead organism get back in to the atmosphere.

Hence, the correct answer is "A. Decomposers breaking down the material".