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': 'Annular Ring scotoma is seen in: \nSelect and explain. \nA. Retinitis pigmentosa, B. Night blindness, C. Severe myopia, D. Angle closure glaucoma', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Retinitis pigmentosa', 'role': 'assistant'}]