This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Miscellaneous, Subject name: Surgery
Investigation of choice in spontaneous Sub arachnoid bleed 
Select and explain. 
A. CT scan, B. Ventriculography, C. Ultrasound, D. Cerebral angiography
A: CT scan
Answer: A: CT scan 
Explanation: (A) CT scan