This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Muscle relaxants, Subject name: Anaesthesia
[{'content': 'Long acting non-depolarising competitive blocker is \nSelect and explain. \nA. Doxacurium, B. Rocuronium, C. Mivacurium, D. Atracurium', 'role': 'user'}, {'content': 'Answer: A \nExplanation: None', 'role': 'assistant'}]