This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Opioids, Subject name: Pharmacology
[{'content': 'The effect of morphine which has least tolerance is? \nSelect and explain. \nA. Analgesia, B. Respiratory depression, C. Constipation, D. Bradycardia', 'role': 'user'}, {'content': 'Answer: C \nExplanation: ANSWER: (C) ConstipationREF: KDT 6th edition page 457Tolerance is exhibited to all actions except meiosis and constipation', 'role': 'assistant'}]