This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Fluid & Electrolyte, Subject name: Pediatrics
[{'content': 'GFR is calculated as: \nSelect and explain. \nA. GFR (ml/minute per 1.73 m2) = kxheight/serum creatinine, B. GFR (ml/minute per 1.73 m2) = kxweight/serum creatinine, C. GFR (ml/minute per 1.73 m2) = k/weightxcreatinine, D. GFR (ml/minute per 1.73 m2) = k/heightxcreatinine', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Ans. A. GFR (ml/minuteper1.73m2)=kxheight/serumcreatinineAn accurate and reliable method for assessment of renal function is essential for children with kidney diseases. Serum creatinine based equations for estimating glomercular filtration rate (GRF) are useful for diagnosis of chronic kidney disease (CKD). Cystatin is another molecule studied for estimating GFR. Cystatin C is an endogenous marker of renal function; its whole blood levels are not affected by age, sex and nutrition . Serum cystatin C is considered to be a more sensitive marker than creatinine in patients with moderate decrease in GFR', 'role': 'assistant'}]