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': 'A 40 year old male patient complains of decayed teeth. Class II cavity preparation was done under rubber dam isolation. Who introduced this method of isolation in dentistry? \nSelect and explain. \nA. Sanford Barnum, B. S. S. White, C. Delous Palmer, D. Jones and Reid', 'role': 'user'}, {'content': 'Answer: A \nExplanation: In 1864, S.C. Barnum, a New York City dentist, introduced the rubber dam into dentistry.\u200b\nReference: Sturdevant’s Art and Science of Operative Dentistry, Mosby, 4th Edition, Page No: 445', 'role': 'assistant'}]