This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Intracranial Space Occupying Lesion, Subject name: Medicine
Which brain tumor has the worst prognosis in children? 
Select and explain. 
A. Cerebellar astrocytoma, B. Brainstem glioma, C. Craniopharyngioma, D. Pineal body tumor
B: Brainstem glioma
Answer: B: Brainstem glioma 
Explanation: Brainstem glioma Aggressive and dangerous cancer Has worst prognosis. Without treatment life expectancy is typically few months from the time of diagnosis.