A 40 year old female presents with a history of sudden onset of headache and nausea which passed off with rest and analgesics.Later she developed blurring of vision for a few days.On the day of admission she had developed third nerve palsy with neck rigidity.The temperature was 100 Degree F. The most likely diagnosis is -

• A. Acute attact of migraine
• B. Viral encephalitis
• C. Sub-arachnoid haemorrhage
• D. Severe hypertension