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: Medicine
Most common cause of acute arterial occlusion 
Select and explain. 
A. Pulmonary emboli, B. Atherosclerosis plaque, C. Emboli atrial fibrillation, D. Thrombosis of aneurysm
C: Emboli atrial fibrillation
Answer: C: Emboli atrial fibrillation 
Explanation: None