This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Kidney and ureter, Subject name: Surgery
The most sensitive imaging modality to detect early renal tuberculosis is: 
Select and explain. 
A. Intravenous urography, B. Computed tomography, C. Ultrasound, D. Magnetic resonance imaging
A: Intravenous urography
Answer: A: Intravenous urography 
Explanation: Genitourinary tuberculosis Investigations- Urine routine and microscopic examination- presence of pus cells- Urine culture and sensitivity- no growth within 48 hours. (Sterile Pyuria- characteristic feature of GU TB)- IOC for diagnosis of renal TB-CECT- Most sensitive investigation to detect the earliest changes in renal TB- IVP (aka IVU)