This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: All India exam, Subject name: Dental
[{'content': 'The patch test is read after \nSelect and explain. \nA. 2 hours, B. 2 days, C. 2 months, D. 2 weeks', 'role': 'user'}, {'content': 'Answer: B \nExplanation: The patch test is read after 48 to 72 hrs and then again after a week. It is read at 20 mins to see any immediate reaction Ref: Harrison 20th edition pg 1256', 'role': 'assistant'}]