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
Risk factor for bladder carcinoma is 
Select and explain. 
A. Clonorcis sinensis, B. Schistosoma hematobium, C. Plasmodium, D. None
B: Schistosoma hematobium
Answer: B: Schistosoma hematobium 
Explanation: Answer- B. Schistosoma hematobiumCigarette smoking is the main etiological factor.Occupational exposures to chemicalsSchistosoma haemotobiumDrugs such as phenacetin & chlornaphazineCyclophosphamidetherapyPelvic radiation