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: Surgery
[{'content': 'Type of renal stone formed in a patient with regional enteritis: \nSelect and explain. \nA. Calcium oxalate, B. cysteine, C. Struvite, D. Urate', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Calcium oxalate stone is formed in patient with Regional enteritis Regional enteritis causes decreased Bile salt absorption, thus Ca++ sequestration and increased absorption of Oxalate', 'role': 'assistant'}]