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: Physiology
[{'content': 'The tubuloglomerular feedback is mediated by: \nSelect and explain. \nA. Sensing of Na+ concentration in the macula densa, B. Sensing of Cl+ concentration in macula densa, C. Sensing NaCl concentration in the macula densa, D. Opening up of voltage gated Na+ channels in afferent aeriole', 'role': 'user'}, {'content': "Answer: C \nExplanation: C i.e. Sensing NaC1 concentration in the macula densa'To perform the function of auto regulation, the kidneys have a feed back mechanism (tubuloglomerular feed back) that links changes in sodium chloride concentration at the macula densa (tubular component) with the control of renal aeriolar resistance. (glomerular component).", 'role': 'assistant'}]