This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Biochemistry
[{'content': 'Polypetide chain termination is enhanced by: \nSelect and explain. \nA. Stop codon, B. Promoter, C. Ribosomal unit, D. All', 'role': 'user'}, {'content': 'Answer: A \nExplanation: A i.e. Stop Codon;', 'role': 'assistant'}]