This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: All India exam, Subject name: Pathology
[{'content': 'Most common cause of leukocoria in newborn is \nSelect and explain. \nA. Congenital cataract, B. Toxocara infection, C. Retinoblastoma, D. CMV infection', 'role': 'user'}, {'content': 'Answer: A \nExplanation: .', 'role': 'assistant'}]