Provides the support for the bases in the structure of DNA.

A. Phosphate
B. Sugar
C. both phosphate and sugar

C. both phosphate and sugar

Explanation:

DNA is made up of two strands, each made of nucleotides. Each nucleotide, in turn, is composed of a sugar (deoxyribose), a phosphate group, and a nitrogenous base. There are four nitrogenous bases: adenine (A), thymine (T), cytosine (C), and guanine (G). DNA takes a double helix shape, like a spiral staircase where the sides are chains of sugars and phosphates connected by steps, which are the nitrogenous bases.

C. BOTH PHOSPHATE AND SUGAR

Explanation:

The four nitrogenous bases that form the DNA are adenine, guanine, cytosine, thymine. Cytosine and thymine are pyrimidines while adenine and guanine are categorized as purines. These bases forms the DNA double helical structure through weak hydrogen bonds between the two opposite strand of the DNA and they complement each other as adenine is always paired with thymine by two hydrogen bonds and cytosine with guanine with three hydrogen bonds. In the DNA, nitrogenous bases are supported by the deoxyribose sugar and phosphate group. They are joined together by covalent bonds called phosphodiester bonds between the sugar of one nucleotide and the phosphate group of the other. This provides for the double helical structure of DNA.