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: Anaesthesia
[{'content': 'Which is safest to be used in asthmatic patients – \nSelect and explain. \nA. Nitrazepam, B. Phenobarbitone, C. Chloral hydrate, D. All hypnotics are safe', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Safe in asthma → Propofol, etomidate, ketamine, vecuronium, rocuronium, Pancuronium, Halothane, Sevoflurane, Desflurane, Isoflurane, Pethidine, Fentanyl, Alfentanil, Benzodiazepines (Nitrazepam).', 'role': 'assistant'}]