Answer: Subarachnoid
Explanation:
The space in the meninges below the arachnoid membrane and above the pia mater contains the cerebrospinal fluid. Cerebrospinal fluid is produced by choriod plexus( a cluster of capillaries) from the blood. Blood vessels traveling within the subarachnoid space deliver oxygen and nutrients to the spinal cord.
Blood vessels present within pia mater space transports oxygen and nutrients to spinal cord.
Pia mater is internal layer of meninges which is in direct contact with and intently covers spinal cord and cerebral cortex. The pia mater has a rich inventory of veins, which give supplements and oxygen to sensory tissue. This layer additionally holds the choroid plexus, a system of vessels and ependyma which is involved in production of cerebrospinal liquid.
Pia mater covering the spinal line is made out of two layers, an external layer comprising of collagen strands and an internal layer that encases the whole spinal rope.
