Correct answer: c) Backbone—a phosphate group and a sugar
d) Rungs—bases
The DNA molecule is made up of a molecule called as a nucleotide. It consists of a Phosphate group, nitrogenous base, and a sugar group.
Each nucleotide molecule contains the four nitrogenous bases called as guanine [G], cytosine [C], adenine [A] and thymine [T], the pentose sugar and a phosphate group.
The rungs of the DNA strand are made up of nitrogenous bases and backbone of the DNA strand are composed of sugar and phosphate group.
