Answer:
Carbon dioxide
Step-by-step explanation:
The major byproduct of fossil fuel combustion is carbon dioxide. When fossil fuels such as coal, oil, and natural gas are burned, they release carbon dioxide into the atmosphere. This is because fossil fuels are made up of hydrocarbons, which are compounds made up of carbon and hydrogen. When these compounds are burned, they react with oxygen in the air to produce carbon dioxide
and water vapor
.
Methane is also produced during fossil fuel combustion, but in smaller amounts compared to carbon dioxide. Sulfuric acid is not a byproduct of fossil fuel combustion, but rather a product of the reaction between sulfur dioxide
and water vapor in the atmosphere. While water vapor is also produced during fossil fuel combustion, it is not considered a major byproduct, as it is a natural component of the air and atmosphere.