Question

which of these fluids is found within the membranous labyrinth of the inner ear? endolymph cochleolymph perilymph

Explanation:

The membranous labyrinth of the inner - ear contains endolymph. Perilymph surrounds the membranous labyrinth, and cochleolymph is not a standard term for inner - ear fluids in this context.

Answer:

Endolymph