This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Dental
[{'content': 'The approximate time in which ferric sulphate dampened in a cotton pellet is put to the root stump while performing pulpotomy is \nSelect and explain. \nA. 10-15 secs, B. 60-90 secs, C. 2-3 mins, D. 4-5 mins', 'role': 'user'}, {'content': 'Answer: A \nExplanation: None', 'role': 'assistant'}]