Which of the following is a characteristic of ribosomal RNA (rRNA)?

Ribosomal RNA (rRNA) plays a crucial role in protein synthesis by serving as a fundamental component of ribosomes, which are the cellular structures where proteins are synthesized. Ribosomes consist of both rRNA and proteins, and the rRNA provides a structural framework for the ribosome, as well as participating in the catalysis of peptide bond formation during translation. This function is vital for the assembly of amino acids into polypeptide chains based on the sequence of messenger RNA (mRNA).

The other options refer to roles performed by different types of RNA. While encoding protein information is a function associated with messenger RNA (mRNA), transporting amino acids is done by transfer RNA (tRNA). The initiation of gene transcription is primarily the role of RNA polymerase and not a function of rRNA. Thus, identifying rRNA as a component of ribosomes captures its essential and unique role in the cellular machinery for protein synthesis.