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
Muscle relaxant excreted exclusively by kidney – 
Select and explain. 
A. Gallamine, B. Atracurium, C. Vercuronium, D. Sch
A: Gallamine
Answer: A: Gallamine 
Explanation: Muscle relaxant entirely dependent on renal excretion are gallamine and metocurine → contraindicated in renal failure.