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
Most common cause of embolic stroke is? 
Select and explain. 
A. Intra cardiac mural thrombi, B. Paiculate matter from iv drug injections, C. Protein C deficiency, D. Antiphospholipid syndrome
A: Intra cardiac mural thrombi
Answer: A: Intra cardiac mural thrombi 
Explanation: *approximately 20% of ischemic strokes are due to embolism from the hea. the most common causes are atrial fibrillation,prosthetic hea valves,other valvular abnormalities and recent myocardial infraction. Ref Harrison20th edition pg 2345