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': 'Alarm system (a reminder technique for digit sucking in mature children) was developed by: \nSelect and explain. \nA. Massler, B. Norton and Gellin, C. Benjamin, D. Pinkham', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Norton and Gellin developed 3 alarm system.', 'role': 'assistant'}]