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: Surgery
Commonest type of cancer of the renal pelvis and upper ureter is - 
Select and explain. 
A. Transitional cell carcinoma, B. Adenocarcinoma, C. Squamous cell carcinoma, D. Nephroblastoma
A: Transitional cell carcinoma
Answer: A: Transitional cell carcinoma 
Explanation: None