What does the abbreviation DNA stand for?

The abbreviation DNA stands for Deoxyribonucleic acid, which is the molecule that carries the genetic instructions necessary for the growth, development, functioning, and reproduction of all known living organisms and many viruses.

DNA is structured as a double helix, composed of two long strands of nucleotides twisted around each other. Each nucleotide contains a phosphate group, a sugar molecule (deoxyribose), and one of four nitrogenous bases (adenine, cytosine, guanine, or thymine). It is this sequence of bases that encodes the genetic information.

This answer is well-supported in the field of genetics and biology, as it reflects widely accepted scientific knowledge. The other options presented do not accurately represent the composition or the correct terminology associated with DNA, as they either describe non-existent or unrelated structures.