This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Head and neck, Subject name: Surgery
[{'content': 'Most common site of sub ependymal astrocytoma (Giant cell): \nSelect and explain. \nA. Trigone of lateral ventricle, B. Foramen of Monro, C. Temporal horn of lateral Ventricle, D. 4th Ventricle', 'role': 'user'}, {'content': 'Answer: B \nExplanation: SubEpendymal Giant cell Astrocytoma Most common site of subependymal giant cell astrocytoma is the ependymal wall of lateral ventricle near the foramen of Monro Causes obstruction at the foramen of Monro leading to ventricular enlargement and raised ICT Presence of multiple periventricular calcific foci (calcified subependymal nodules) suggest the diagnosis of Tuberous sclerosis with subependymal giant cell astrocytoma Ref: Neurology in Clinical practice 4th edition Pgno: 428', 'role': 'assistant'}]