Answer;
-Driving cars
Humans add greatly to the carbon cycle by driving cars.
Explanation;
Humans contribute greatly to the change sin the carbon cycle. Humans are moving more carbon into the atmosphere from other parts of the Earth system. More carbon is moving to the atmosphere when fossil fuels, like coal and oil, are burned.
More carbon is moving to the atmosphere as humans get rid of forests by burning the trees.Burning wood releases carbon into the atmosphere that had been stored in the tree