The correct answer is C. DNA molecules.
DNA is a molecule that contains the genetic instructions for an organism. It is made up of four types of nucleotides: adenine (A), thymine (T), guanine (G), and cytosine (C). The order of these nucleotides in DNA determines the organism’s genetic code.
The genetic code is a set of instructions that tells the cell how to make proteins. Proteins are the building blocks of cells and tissues, and they are responsible for carrying out many of the body’s functions.
The inherited traits of an organism are determined by the organism’s DNA. When an organism reproduces, its DNA is passed down to its offspring. This is how traits are passed down from generation to generation.
RNA molecules are also involved in the process of gene expression, but they do not contain the genetic instructions for an organism. Enzymes are proteins that catalyze chemical reactions, but they do not contain the genetic instructions for an organism.