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: Radiology
[{'content': 'Which of the following is the most common cause of a mixed cystic and solid suprasellar mass seen on cranial MR scan of a 10-year-old child? \nSelect and explain. \nA. Pituitary adenoma, B. Craniopharyngioma, C. Optic chiasmal glioma, D. Germinoma', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Ans. Craniopharyngioma', 'role': 'assistant'}]