Which biomolecule category includes DNA and RNA?

• A. Proteins
• B. Carbohydrates
• C. Lipids
• D. Nucleic acids

Answer: (D)

DNA and RNA are nucleic acids. This category is defined by polymers built from nucleotides, each with a sugar, a phosphate group, and a nitrogenous base. The sugar–phosphate backbone forms long chains through phosphodiester bonds, and the sequence of bases stores genetic information. DNA typically serves as the long-term genetic blueprint, usually double-stranded, while RNA is usually single-stranded and helps convert that information into proteins and other cellular roles. This sets nucleic acids apart from proteins (made of amino acids with diverse structures and functions), carbohydrates (sugars used mainly for energy and structure), and lipids (fats and related molecules that form membranes and store energy).