A nucleotide is composed of which components?

• A. Sugar, Phosphate, Nitrogenous base
• B. All of the above
• C. Only sugar
• D. Only phosphate

Answer: (B)

A nucleotide contains three essential parts: a sugar, a phosphate group, and a nitrogenous base. The sugar provides the carbon backbone, the phosphate connects sugars together to form the backbone of DNA or RNA, and the nitrogenous base carries the genetic information through base pairing. Since a nucleotide is defined by having all three components, the option that includes sugar, phosphate, and nitrogenous base is the correct one. The other choices mention only one component, which does not describe a complete nucleotide.