What is petroleum primarily used as?

Petroleum is primarily used as fuel for cars due to its composition as a fossil fuel that is rich in hydrocarbons. When refined, petroleum products, such as gasoline, diesel, and jet fuel, are created, which are essential for the transportation sector. The combustion of these fuels in internal combustion engines provides the energy needed to power vehicles. This widespread application as a primary energy source for transportation makes petroleum a critical component of modern infrastructure and mobility.

Other uses of petroleum do exist, such as being a raw material for producing a variety of chemicals and products, but its most significant and recognizable application is in fueling automobiles and other transport systems. The other options either relate to different types of energy sources, specific uses of petroleum that are not as primary, or entirely different categories of substances.