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': 'According to ADA specification of a tooth-brush, which of the following is false? \nSelect and explain. \nA. Head of the brush should be 2 inches long, B. 2-4 rows of bristles, C. 5-12 tufts per row, D. 80-86 bristles per tuft', 'role': 'user'}, {'content': 'Answer: A \nExplanation: None', 'role': 'assistant'}]