The answer is letter C. The sides of the DNA molecule, the rails of the
ladder, are composed of phosphates and sugars.
DNA strands constitute chemicals called nucleotides. DNA molecules on the other
hand are made up of 2 polynucleotide chains. This polynucleotide is
arranged on the backbone, the double helix. These nucleotides
(polynucleotide and nucleotides) are composed of three parts: a phosphate, a
sugar (deoxyribose), and a type of compound base.
Deoxyribose
and phosphate creates the backbone of the side of the ladder, nucleic acid
while the base join both polynucleotide chains like the rungs of the ladder.
