This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Special Senses: Hearing and Equilibrium, Subject name: Physiology
[{'content': '| ECF K+ levels are seen in \nSelect and explain. \nA. Ectolymph, B. Aqueous humour, C. Endolymph, D. Vitreous humour', 'role': 'user'}, {'content': 'Answer: C \nExplanation: (C) Endolymph # Endolymph is formed in the scala media by the stria vascularis and has a high concentration of K+ and a low concentrtion of Na+.> Cells in the stria vascularis have a high concentration of Na+-K+ATPase.> In addition, it appears that there is a unique electrogenic K+ pump in the stria vascularis, which accounts for the fact that the scala media is electrically positive by 85 mV relative to the scala vestibuli and scala tympani.', 'role': 'assistant'}]