Which molecules are the largest in the body and contain DNA and RNA?

The correct choice identifies nucleic acids as the largest molecules in the body that contain DNA and RNA. Nucleic acids are macromolecules made up of long chains of nucleotides, which include a sugar, a phosphate group, and a nitrogenous base. These molecules serve as the fundamental building blocks of genetic material, with DNA storing and transmitting genetic information and RNA playing critical roles in protein synthesis and various regulatory processes within cells.

Proteins, while also large macromolecules essential for numerous biological functions, do not contain DNA or RNA; rather, they are composed of amino acids and perform a wide array of tasks, including enzyme activity, structural support, and signaling. Carbohydrates and lipids are important for energy storage and cellular structure but do not encompass the genetic material that nucleic acids do, nor are they classified as the largest molecules associated with DNA and RNA.