This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: General pathology, Subject name: Pathology
[{'content': 'Myocardial infarction shows fibrosis. What is the duration? \nSelect and explain. \nA. 2 days, B. 5 days, C. 1 week, D. 3 weeks', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Fibrosis after MI sets in by 5 days. Basic Pathology, Robbins. Page no.: 380', 'role': 'assistant'}]