The correct answer will be Nucleotides.
Both DNA and RNA are the nucleic acids which act as genetic material of the cell.
Both nucleic acids, DNA and RNA are made of monomer unit called nucleotides or nucleoside monophosphates. Every nucleotide is made up of three components: a nitrogenous base, a pentose (5-carbon) sugar, and a phosphate group.
Monomer units shows 2 differences in both nucleic acids :
1. Nitrogenous bases– in DNA bases are guanine, adenine, thymine and cytosine or while RNA differs by 1 base which is uracil instead of thymine.
2. Pentose sugar- in DNA sugar is deoxy-ribose due to loss of one oxygen group from 2’OH while in RNA it is ribose with 2’OH.
thus, Nucleotides is the correct answer.