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': 'Most common presentation of Retinoblastoma \nSelect and explain. \nA. Strabismus, B. Leucocoria, C. Decreased vision, D. Yellowish-white retinal mass.', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Leucocoria (60%)\nStrabismus (22%)\nDecreased vision (5%).', 'role': 'assistant'}]