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': 'Long acting b2 sympathomimetic ? \nSelect and explain. \nA. Salmeterol, B. Orciprenaline, C. Penoterol, D. Pexbaterol', 'role': 'user'}, {'content': "Answer: A \nExplanation: Ans. is 'a' i.e., Salmeterol o b2-agonistsused in Asthma 1.Sho acting --> Salbutamol, terbutaline 2. Long acting --> Salmeterol, formoterol", 'role': 'assistant'}]