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': 'The most common second malignant in survivors of retinoblastoma is – \nSelect and explain. \nA. Thyroid cancer, B. Nasopharyngeal carcinoma, C. Optic glioma, D. Osteosarcoma', 'role': 'user'}, {'content': 'Answer: D \nExplanation: Most common secondary tumor in survivors of retinoblastoma is osteosarcoma.', 'role': 'assistant'}]