This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: C.V.S, Subject name: Medicine
[{'content': 'True regarding atrial fibrillation - \nSelect and explain. \nA. | Thromboembolism, B. adrenaline treatment, C. Anticoagulant not required, D. Aspirin given', 'role': 'user'}, {'content': 'Answer: A \nExplanation: thromboembolism is a feature of atrial fibrilation anticoagulant is given but aspirin is not used adrenaline is contraindicated Ref Harrison 20th edition pg 1443', 'role': 'assistant'}]