This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Nervous System, Subject name: Surgery
A 48-years old woman comes with bilateral progressive weakness of both lower limbs, spasticity and mild impairment of respiratory movements. MRI shows an intradural mid-dorsal midline enhancing lesion. What is the diagnosis? 
Select and explain. 
A. Intradural lipoma, B. Meningioma, C. Neuroenteric cyst, D. Dermoid cyst
B: Meningioma
Answer: B: Meningioma 
Explanation: Ans. (b) MeningiomaCNS tumors can be Intra axial or Extra axial:Intra axial:* Neuronal* Astrocytoma* Lymphoma Extra axial:* Pituitary* Schwannoma* Meningioma