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
Dye for myelography is injected in which space : 
Select and explain. 
A. Subdural, B. Epidural, C. Subarachnoid, D. Extradural
C: Subarachnoid
Answer: C: Subarachnoid 
Explanation: Myelography is the radiographic investigation of the spinal canal for the diagnosis of space occupying an obstructive lesion. It requires the contrast agent to be injected  into subarachnoid space.
MRI has replaced myelography, these days.