What do hydrocarbons consist of?

Hydrocarbons are organic compounds that are primarily composed of hydrogen and carbon atoms. The defining characteristic of hydrocarbons is their structure, which can range from simple molecules like methane (CH₄) to complex molecules like those found in petroleum. The presence of only carbon and hydrogen allows hydrocarbons to exist in various forms, such as alkanes, alkenes, and alkynes, depending on the types of bonds present between the carbon atoms.

This distinction is crucial in understanding the chemical behavior and properties of hydrocarbons, which serve as fundamental building blocks in organic chemistry, including fuels, plastics, and many biological molecules. Other options involve elements that are not part of the hydrocarbon definition, which clearly establishes why they do not accurately describe hydrocarbons.