What is the primary function of RNA in a cell?

The primary function of RNA in a cell is to make proteins. This process starts with transcription, where messenger RNA (mRNA) is synthesized from a DNA template. The mRNA carries the genetic instructions from DNA to the ribosomes, which are the sites of protein synthesis. Once at the ribosome, transfer RNA (tRNA) reads the sequence of the mRNA and brings the appropriate amino acids to form a polypeptide chain. This sequence of events illustrates that RNA plays a crucial role in translating genetic information into functional proteins, which are essential for numerous cellular processes and functions.

While other choices mention important biological processes, they do not accurately describe RNA's primary function. Genetic information is mainly stored in DNA, while energy provision is typically associated with ATP and other molecules. Nutrient transport is usually a role fulfilled by various proteins and transporters, not RNA. Thus, the role of RNA in protein synthesis is fundamental and central to cellular function.