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: Pharmacology
[{'content': "Which of the following drug doesn't act on thyroid? \nSelect and explain. \nA. Propranolol, B. Propylthiuracil, C. Sodium iodide, D. Thiocyanote", 'role': 'user'}, {'content': "Answer: A \nExplanation: Ans. is 'a' i.e., Propranolol", 'role': 'assistant'}]