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
Commonest spinal tumour is 
Select and explain. 
A. Neuroblastomas, B. Neurofibroma, C. Ependymoma, D. Meningioma
B: Neurofibroma
Answer: B: Neurofibroma 
Explanation: Remember: Most Common Spinal tumor - Metastasis Primary spinal tumor - Nerve sheath tumor (Neurofibromas, Schwannoma Extradural tumor - Metastasis Intradural extramedullary - Nerve sheath tumor Intramedullary - Ependymoina Ref : Schwaz surgery 7/e p1891