1. D 2. A) Could contain the nitrogenous base thymine: nucleotide, DNA, polynucleotide, nucleotide, DNA polymerase B) The monomers of nucleic acids: nucleotides C) Forms the covalent bonds between nucleotides: DNA polymerase D) Formed by covalent bonds forming between nucleotides: sugar phosphate backbone E) A polymer of nucleotides: DNA, RNA F) Could contain the nitrogenous base adenine: nucleotide, DNA, RNA polynucleotide, nucleotide, DNA polymerase 3. A, C, G, and T. The bases can be divided into thymine and cytosine, which are single-ring structures, and adenine and guanine structures, larger and double-ring structures.