This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Inflammatory Bowel Disease, Subject name: Medicine
[{'content': 'Ulcterative colitis associated features include all except: \nSelect and explain. \nA. Iritis, B. Ahritis, C. Urethritis, D. Pyoderma', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Bloody diarrhea is the hallmark feature of ulcerative colitis. Extracolonic manifestations include: Erythema nodosum Pyoderma gangrenosum Episcleritis Iritis Thrombo-embolic events Oligo-aicular, non-deforming ahritis. In patients who are HLA B27-seropositive, there may be anterior uveitis or ankylosing spondylitis which is independent of colitis activity.', 'role': 'assistant'}]