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
A patient with history of weakness of one side was brought to AIIMS emergency medicine department with altered sensorium. A CT was taken, and showed the following. What should be done next? 
Select and explain. 
A. Decompressive craniotomy, B. Intravenous mannitol, C. Observe and follow-up, D. Aspirin
B: Intravenous mannitol
Answer: B: Intravenous mannitol 
Explanation: ANS. B