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': "A young patient presents to the ophthalmology clinic with loss of central vision. ERG is normal but EOG is abnormal. Which of the following is the most likely diagnosis: \nSelect and explain. \nA. Stargardt's disease, B. Best's vitelliform dystrophy, C. Retinitis pigmentosa, D. Cone-rod dystrophy", 'role': 'user'}, {'content': "Answer: B \nExplanation: Ans. Best's vitelliform dystrophy", 'role': 'assistant'}]