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: Medicine
Ove symptoms of Renal failure become evident when Renal Function Deteriorates by more than 
Select and explain. 
A. 40-50%, B. 50-60%, C. 70-80%, D. >90%
C: 70-80%
Answer: C: 70-80% 
Explanation: Answer is C (70-80%) Ove symptoms usually develop only after renal function has deteriorated by >75 - 80% (residual renal function <20%).