This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: All India exam, Subject name: Physiology
[{'content': 'GFR is best measured with which of the following? \nSelect and explain. \nA. Iodohippurate, B. Tc99m-DTPA, C. Tc99m-MAG3, D. Tc99m-DMSA', 'role': 'user'}, {'content': "Answer: C \nExplanation: Tc-99m MAG3 (mercaptoacetyltriglycine) is one of the technetium radiopharmaceuticals used in renal imaging. ... excretion: renal both glomerular filtration and tubular excretion; Ref ganong's review of medical physiology 25e", 'role': 'assistant'}]