This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Pathology
Commonest cause of Cerebral Infarction is: 
Select and explain. 
A. Aerial thrombosis, B. Aeritis, C. Venous thrombosis, D. Lymphangitis
A: Aerial thrombosis
Answer: A: Aerial thrombosis 
Explanation: Aerial thrombosis