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: ENT
The function of stria vascularis is: 
Select and explain. 
A. To produce perilymph, B. To absorb perilymph, C. To maintain electric milieu of endolymph, D. To maintain electric milieu of perilymph
C: To maintain electric milieu of endolymph
Answer: C: To maintain electric milieu of endolymph 
Explanation: Scala vestibuli and scala tympani are filled with perilymph, whereas scala media/membranous cochlea is filled with endolymph.