Which of the following is an example of hydrocarbons containing double bonds?

Hydrocarbons that contain double bonds are classified as alkenes. These compounds have at least one carbon-carbon double bond in their molecular structure. The formula for an alkene can generally be represented as CnH2n, where n is the number of carbon atoms. This formula reflects the presence of the double bond, which reduces the number of hydrogen atoms in comparison to alkanes, which are saturated hydrocarbons with single bonds only.

Looking at the molecular formula for the choice identified as the correct answer, C4H8, it aligns perfectly with the general formula for alkenes. With four carbon atoms (n=4), the formula CnH2n produces C4H8, confirming that this compound indeed contains a double bond.

In contrast, the other options contain either single bonds or do not adhere to the alkene formula. For example, C2H6 (an alkane) follows the CnH2n+2 formula, indicating it is fully saturated with hydrogen and has only single bonds. Similarly, C6H10 and C8H12 also are alkenes, but the question specifically asks for an example of hydrocarbons containing double bonds, where C4H8 fits that definition as