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: Psychiatry
[{'content': 'The follwing are opioid withdrawl symptoms except: \nSelect and explain. \nA. Insomnia, B. Piloerection, C. Rhinorrhea, D. Constipation', 'role': 'user'}, {'content': 'Answer: D \nExplanation: D i.e. Constipation', 'role': 'assistant'}]