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
BCG used as treatment for which cancer 
Select and explain. 
A. Lung, B. Bladder, C. Rectum, D. Gall bladder
B: Bladder
Answer: B: Bladder 
Explanation: BCG is used as intravesical chemotherapeutic agent.