when fossil fuels are burned they cause an increase in which gas

carbon dioxide
methane
oxygen

1 answer

When fossil fuels are burned, they cause an increase in carbon dioxide. This is a major contributor to greenhouse gas emissions and is a significant factor in climate change. Methane is also a greenhouse gas but is not directly emitted from the burning of fossil fuels; it is released during the extraction and transportation of fossil fuels. Oxygen is consumed in the combustion process.