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
Condition which causes colonic carcinoma 
Select and explain. 
A. Ulcerative colitis, B. Crohn's disease, C. EM, D. Pemphigoid
A: Ulcerative colitis
Answer: A: Ulcerative colitis 
Explanation: None