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: Radiology
A patient presents with acute renal failure and anuria. The USG is normal. Which of the following investigation will give best information regarding renal function – 
Select and explain. 
A. Intravenous pyelogram, B. Retrograde pyelography, C. Antegrade pyelography, D. DTPA scan
D: DTPA scan
Answer: D: DTPA scan 
Explanation: Functional renal study is done by DTPA/MAG-3.