Jeremy was asked to describe the impact of humans on the carbon cycle. He answered: "When people drive cars they add more carbon dioxide to the atmosphere." Jeremy only received partial credit for his
answer. Which of the following answers could have received full credit?

Humans add carbon dioxide to the atmosphere when they burn fuel in factories and other biomass sources. Humans take in carbon from the food they eat from the soil and return it back to the soil through waste products and decomposition.

Explanation:

When humans add carbon into the atmosphere the main contributors are burning of substances like fuels and biomass and from eating.

i think the answer is a, hope this is right, that would be my best guess.