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: Ophthalmology
[{'content': 'Horner syndrome causes all, except: \nSelect and explain. \nA. Enophthalmos, B. Mydriasis, C. Anhidrosis, D. Narrowed palpebral fissure', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Mydriasis', 'role': 'assistant'}]