Which of the following elements, when combined, form a hydrocarbon?

Hydrocarbons are organic compounds that consist solely of hydrogen and carbon atoms. When examining the elements that contribute to the structure of hydrocarbons, it's important to recognize that they are specifically formed through the bonding of hydrogen and carbon.

In the context of this question, the pairing of carbon with hydrogen produces a variety of hydrocarbons, such as alkanes, alkenes, and alkynes, which are essential classes of organic compounds. These compounds are significant in both natural and synthetic processes, particularly as fuels, solvents, and in the creation of various plastics and chemicals.

While combinations involving other elements, such as oxygen, may form different types of compounds, they do not meet the definition of hydrocarbons. Therefore, the option that correctly identifies the elements that exclusively combine to form hydrocarbons is the combination of carbon and hydrogen.