This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Pancreas, Subject name: Surgery
[{'content': 'Best method of localization of insulinoma:- \nSelect and explain. \nA. EUS with intra-operative palpation, B. MRI with dynamic CT, C. SRS, D. CECT', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Localization of insulinoma Gold Standard Investigation - 72 hours fasting Insulin/ Glucose (ratio) > 0.4 is diagnostic Best pre-op Test for localization- Intra Aerial Ca+ injection with poal venous blood sampling Overall best Investigation for localization - EUS along with "Intra-Op Palpation"', 'role': 'assistant'}]