This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Magnetic Resonance Imaging, Subject name: Radiology
[{'content': 'Which MRI sequence is called as Tractography? \nSelect and explain. \nA. DWI, B. SWI, C. DTI, D. FLAIR', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Tractography: Is a 3D modelling technique used to visually represent nerve tracts using data collected by Diffusion Tensor Imaging. It uses special techniques of magnetic resonance imaging (MRI) and computer-based diffusion tensor imaging.', 'role': 'assistant'}]