Question

what is the filum terminale formed from?
dura mater
arachnoid mater
pia mater
spinal nerves

Explanation:

The filum terminale is a non - neural fibrous band. It is formed from the pia mater. The pia mater is the innermost of the three meninges (dura mater, arachnoid mater, pia mater) that cover the spinal cord. The dura mater is the tough outer layer, the arachnoid mater is the middle layer, and spinal nerves are part of the peripheral nervous system and not related to the formation of the filum terminale.

Answer:

Pia mater