This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: GIT and hepatobiliary system, Subject name: Radiology
[{'content': '"Coffee bean" sign is seen in - \nSelect and explain. \nA. Intussusception, B. Bowel ischaemia, C. Sigmoid volvulus, D. Congenital hyperophic pyloric stenosis', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Description : Intussusception: usg signs : target sign ,pseudokidney sign, crescent in a doughnut sign Bowel ischemia signs: pneumatosis intestinalis , pneumatosis poalis. Sigmoid volvulous :X- ray :coffee bean sign,frimann-dahl sign; CT scan : whirl sign and birds beak sign CHPS : on fluoroscopy caterpillar sign, string sign, double track sign', 'role': 'assistant'}]