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
[{'content': 'The most sensitive test to detect GI bleeding is ? \nSelect and explain. \nA. Selective angiography, B. Radiolabelled, erythrocyte scanning, C. Fibrinogen studies, D. Stool for occult blood', 'role': 'user'}, {'content': "Answer: B \nExplanation: Ans. is 'b' i.e., Radiolabelled, erythrocyte scanning", 'role': 'assistant'}]