This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: G.I.T, Subject name: Surgery
[{'content': 'Glod standard test for insulinoma \nSelect and explain. \nA. 72 hr fasting test, B. Plasma insulin levels, C. C-peptide levels, D. Low glucose levels < 30 mg\\/dl', 'role': 'user'}, {'content': 'Answer: A \nExplanation: A fasting test that may last for up to 72 hrs is regarded as the most sensitive test.Usually , insulin, pro insulin, C-peptide and blood glucose are measured in 1- to 2-hr intervals to demonstrate inappropriately high secretion of insulin on relation to blood glucose. About 80% of insulinomas are diagnosed by this test,most of them in first 24 hrs . Bailey & Love ,26th,788', 'role': 'assistant'}]