Here's why:

* Polymers are large molecules made up of repeating smaller units called monomers.

* DNA (Deoxyribonucleic acid) is made up of repeating units called nucleotides.

Each nucleotide consists of:

* A sugar molecule (deoxyribose in DNA)

* A phosphate group

* A nitrogenous base (adenine, guanine, cytosine, or thymine)

These nucleotides link together in a long chain, forming the DNA polymer.

Let me know if you'd like to learn more about the structure of DNA!