Which of the following describes a compound that has at least one carbon-carbon double bond?

A compound with at least one carbon-carbon double bond is specifically classified as an alkene. Alkenes are hydrocarbons that contain one or more carbon-carbon double bonds (C=C) in their molecular structure. This characteristic double bond is what distinguishes alkenes from other types of hydrocarbons.

Alkanes, in contrast, are saturated hydrocarbons that contain only single bonds (C-C). They do not have any double or triple bonds, which rules them out as being the correct answer. Alkynes are another class of hydrocarbons, but they contain carbon-carbon triple bonds (C≡C) instead of double bonds. Alkyl halides are organic compounds containing carbon, hydrogen, and one or more halogens, but they do not specifically denote the presence of carbon-carbon double bonds and can belong to various hydrocarbon classes, including alkenes and alkanes.

Thus, the definition and properties of alkenes confirm that this is the correct characterization for a compound with one or more carbon-carbon double bonds.