This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Metabolism of protein and amino acid, Subject name: Biochemistry
[{'content': 'Which one of the following enzymes is not a protein, but an RNA molecule \nSelect and explain. \nA. Peptidyl transferase, B. RNA polymerse, C. Restriction endonuclease, D. Reverse transcriptase', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Some RNA molecules have intrinsic catalytic activity. The activity of these RNA enzymes, or ribozymes, often involves the cleavage of a nucleic acid. Two ribozymes are the peptidyl transferase that catalyzes peptide bond formation on the ribosome, and ribozymes involved in the RNA splicingRef: Harper 30th pg: 363', 'role': 'assistant'}]