Which two types of nucleic acids exist within living organisms?

Living organisms contain two primary types of nucleic acids: DNA and RNA. DNA, or deoxyribonucleic acid, is the molecule that carries the genetic blueprint for the development, functioning, and reproduction of all known living organisms and many viruses. It possesses a double-helix structure and is primarily located in the cell nucleus. RNA, or ribonucleic acid, plays critical roles in various biological processes, including protein synthesis and gene expression. There are different forms of RNA, such as messenger RNA (mRNA), transfer RNA (tRNA), and ribosomal RNA (rRNA), each serving distinct functions within the cellular machinery.

The correct answer encompasses the two fundamental types of nucleic acids, as DNA stores genetic information while RNA acts as a functional counterpart in the processes that decode and express that information. Other choices include specific forms of RNA but do not reflect the complete range of nucleic acids present in living organisms. Consequently, they do not represent the full spectrum of nucleic acids crucial for life.