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': 'Laudanosine is a metabolite of : \nSelect and explain. \nA. Atracurium, B. Cis–atracurium, C. Pancuronium, D. Vecuronium', 'role': 'user'}, {'content': 'Answer: A \nExplanation: None', 'role': 'assistant'}]