This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Haematology, Subject name: Medicine
[{'content': 'TRALI occurs within how many hours of transfusion? \nSelect and explain. \nA. 6 hours, B. 12 hours, C. 48 hours, D. 72 hours', 'role': 'user'}, {'content': 'Answer: A \nExplanation: TRALI is defined as Transfusion Associated Acute Lung injury (ALI) that occurs within 6 hours of transfusion with the majority of patients developing clinical features within 1-2 hours of transfusion (Usually 1 to 2 hours but up to 6 hours) Ref: Harrisons 20th edition', 'role': 'assistant'}]