This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: C.N.S., Subject name: Medicine
[{'content': 'Investigation of choice to diagnose epilepsy is: \nSelect and explain. \nA. MRI, B. EEG, C. CT scan, D. Angiogram', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Ans: bRef: Harrison, 16thed, p. 2363- 2364', 'role': 'assistant'}]