What has the greatest human impact on global warming

On Earth, human activities are changing the natural greenhouse. Over the last century the burning of fossil fuels like coal and oil has increased the concentration of atmospheric carbon dioxide (CO2). This happens because the coal or oil burning process combines carbon with oxygen in the air to make CO2.

all fossil fuels are nonrenewable, so think coal, gasoline, things that we will eventually run out of. all fossil fuels are nonrenewable resources, but not all nonrenewable recourses are fossil fuels. these resources are not being renewed as fast as we are using them. i hope this considering there weren't any answer choices.