Concept:Hydrocarbons are compounds containing only carbon and hydrogen. Those with multiple bonds between carbon atoms are classified as unsaturated hydrocarbons.
Solution:- A carbon-carbon double bond (\( \text{C=C} \)) is the defining characteristic of alkenes.
- A carbon-carbon triple bond (\( \text{C}\equiv\text{C} \)) is the defining characteristic of alkynes.
- Therefore, the correct pair of hydrocarbon classes described by the question is alkenes and alkynes.
- Note: The book's answer key table erroneously listed C, but its own explanatory notes correctly identify Alkenes and Alkynes (D) as the intended answer.
Why other options are incorrect:Alcohols and alkyl halides contain oxygen and halogens respectively (not just hydrocarbons). Alkanes and cycloalkanes contain only single sigma bonds.
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