Answer :
Nucleotides, which are the building blocks of nucleic acids, consist of a phosphate group, a nitrogenous base, and a 5-carbon sugar.
Answer;
-5-carbon sugar
Explanation;
-The basic repeating unit of nucleic acids are known as nucleotides. There are two types of nucleic acids, namely RNA and DNA.
-A nucleotide consists of three distinct chemical groups, a 5-carbon sugar (ribose or deoxyribose), a nitrogen-rich base - (cytosine (C), guanine (G), adenine (A), thymine (T) in DNA or uracil (U) instead of T (in RNA), and phosphate.