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: Radiology
Which of the following agents is used to measure Glomerular Filtration Rate 
Select and explain. 
A. Iodohippurate, B. Tc99m-DTPA, C. Tc99m-MAG3, D. Tc99m-DMSA
B: Tc99m-DTPA
Answer: B: Tc99m-DTPA 
Explanation: Tc99m-Diethylene Triamine Pentothenic Acid (DTPA) is an agent of choice widely used in measuring GFR. REF : DAVID SUTTON 7th ed