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 acoustic neuroina : \nSelect and explain. \nA. CT without contrast, B. CT with contrast, C. MR without contrast, D. MR with contrast', 'role': 'user'}, {'content': 'Answer: D \nExplanation: MR with contrast', 'role': 'assistant'}]