This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: All India exam, Subject name: Pharmacology
[{'content': 'Phase I blocker is \nSelect and explain. \nA. Suxamethonium, B. Atracurium, C. Gallamine, D. D-Tubocurare', 'role': 'user'}, {'content': 'Answer: A \nExplanation: The kind of depolarizing block produced by succinyl choline is phase I block. ref: KD Tripathi 8th ed.', 'role': 'assistant'}]