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': 'Muscle relaxant excreted exclusively by kidney – \nSelect and explain. \nA. Gallamine, B. Atracurium, C. Vercuronium, D. Sch', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Muscle relaxant entirely dependent on renal excretion are gallamine and metocurine → contraindicated in renal failure.', 'role': 'assistant'}]