This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Nuclear medicine, Subject name: Radiology
[{'content': 'Radio isotope Preferred for measuring GFR: \nSelect and explain. \nA. OIH, B. DMSA, C. DTPA, D. MAG 3', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Functional / Dynamic Renography * Done with Tc99m DTPA / Tc99m - MAG3 * Tc99m DTPA -evaluate G.F.R * Tc99m MAG3 - evaluate Renal function Renal perfusion Renal plasma flow', 'role': 'assistant'}]