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': 'Acute onset headache, fever, seizure: \nSelect and explain. \nA. Meningitis, B. Migraine, C. Subarachnoid haemorrhage, D. Encephalitis', 'role': 'user'}, {'content': 'Answer: D \nExplanation: (Encephalitis): Ref: 2480, 88, 247-73-2387-H (2621-22-H17th)Meningitis: - Clinical triad fever headache and nuchal rigidity ("Stiff neck") > 90% of cases* Seizures occurs as part of the initial presentation of bacterial meningitis (20 - 40%) of patients* Kernig\'s sign and Brudzinski\'s sign positiveSubarachnoid hemorrhage: -* Most common cause of S AH is rupture of saccular aneurysm* Sudden loss of consciousness, severe headache (generalized, neck stiffness and vomiting/No fever* Common deficits - hemiparesis, aphasia and abulia* Focal deficits frequently absent (995 - CMDT)Migraine: -* Migraine, the most common cause of headache* Headache, nausea, vomiting, photophobia, scalp tenderness is common symptomsEncephalitis: -* Acute febrile illness, meningitis features, confusion, behavioural abnormalities, altered level of consciousness, focal or generalized seizures occurs in severe encephalitis* Focal finding aphasia ataxia, hemiparesis, cranialnerve palcies (ocular palsies, facial weakness) (2480 - H)', 'role': 'assistant'}]