This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Gastrointestinal Radiology, Subject name: Radiology
[{'content': 'Investigation of choice for evaluation of upper abdominal trauma \nSelect and explain. \nA. USG, B. CT, C. SCINTIGRAPHY, D. MRI', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Initial investigation in abdominal trauma is FAST (USG) IOC in Abdominal Trauma - CECT', 'role': 'assistant'}]