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
Investigation of choice for diagnosis and staging of renal cell carcinoma 
Select and explain. 
A. USG, B. CECT, C. IVP, D. MRI
B: CECT
Answer: B: CECT 
Explanation: IOC - CECT.
IOC if renal vein or IVC involved  - MRI.