This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Demyelinating disorder, Subject name: Medicine
[{'content': 'Which of the following tests is not required for the diagnosis of multiple sclerosis? \nSelect and explain. \nA. Lumbar puncture, B. Gadolinium-enhanced MRI, C. Visual evoked potential, D. Electronystagmogram', 'role': 'user'}, {'content': 'Answer: D \nExplanation: Electronystagmogram(ENG) Measures normal eye movement and involuntary rapid eye movements called nystagmus . Checks the muscles, that control eye movements. Checks how well the eyes, inner ears , and brain help you keep your balance and position Revised McDonald criteria for diagnosis of MS following investigation should be done: 1. MRI (Gadolinium-enhanced): Plaques/Dawson Fingers 2. Lumbar puncture-CSF electrophoresis shows Oligo-clonal IgG bands. 3. Visual evoked potential(VEP): shows reduced amplitude of voltage generated due to plaques in optic nerve.', 'role': 'assistant'}]