Consider the picture of the carbon cycle. carbon dioxide is a small portion of the gases in our atmosphere. carbon dioxide is naturally added when organisms respire. it is removed naturally when plants and other producers undergo photosynthesis. what is one way that humans are adding great quantities of carbon dioxide to the atmosphere? use the model to you. what example do you see?

People do release carbon dioxide during respiration and gas exchange. But this does not make a great amount of that plus, the plants requires them for photosynthesis.

However, nowadays people release a large amount of carbon dioxide into the atmosphere due to the operation of factories, and driving cars. The burning of fossil fuels, which generates electricity, is the main reason of the increasing carbon dioxide in atmosphere.

This can lead to greenhouse effect, since carbon dioxide can trap heat inside and still absorb more heat at the same time. And then, global warming occurs and it affects living organisms.

The answer is c : ) hope this answered your question!