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': 'Which of the following has least effect on cardiovascular system - \nSelect and explain. \nA. Gallamine, B. Pancuronium, C. Tubocurarine, D. Atracurium', 'role': 'user'}, {'content': "Answer: D \nExplanation: Ans. is 'd' i.e., Atracurium o Atracurium has no effect on cardiovascular system, so it can be used in patients with altered hemodynamics.", 'role': 'assistant'}]