This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Substance abuse, Subject name: Anatomy
[{'content': 'Which of the following is a symptom of opioid withdrawal \nSelect and explain. \nA. vomiting, B. delirium, C. constipation, D. meiosis', 'role': 'user'}, {'content': 'Answer: A \nExplanation: In opioid withdrawal ALL ORIFICES BLEED Lacrimation, vomiting, rhinorrhea, diarrhea, mydriasis, kicking the habit, muscle cramps, abdominal cramps, tachycardia, cold turkey Ref. kaplon and sadock, synopsis of psychiatry, 11 th edition, 660', 'role': 'assistant'}]