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: Pathology
[{'content': "True regarding Crohn's disease are all except \nSelect and explain. \nA. Scleroderma, B. Transmural involvement, C. Cobble stone appearance, D. Skin involvement", 'role': 'user'}, {'content': "Answer: A \nExplanation: The skin involvement in Crohn's disease causes erythema nodosum, scleroderma does not occur in Crohn's\xa0disease.\n\nOther extraintestinal manifestations of Crohn's disease:\n1. Migratory polyarthritis\xa0\xa0\xa0\xa0\xa0\xa0\xa0\xa0\xa0\xa0\xa0\n2. Sacroiliitis\xa0\n3. Ankylosing spondylitis \xa0 \xa0\n4.\xa0Uveitis\n5.. Hepatic pericholangitis \xa0 \xa0 \xa0 \xa0\n6. Primary sclerosing cholangitis\n7. Clubbing", 'role': 'assistant'}]