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: Radiology
[{'content': 'Investigation of choice for small intestine tumor: \nSelect and explain. \nA. Ba meal follow through, B. Echo, C. X-ray abdomen, D. CT scan with contrast', 'role': 'user'}, {'content': 'Answer: D \nExplanation: Ans. CT scan with contrast', 'role': 'assistant'}]