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': 'Cast perforated resin retained FPD for posterior teeth was first described by \nSelect and explain. \nA. Rochette, B. Livaditis, C. Tanaka, D. Thompson', 'role': 'user'}, {'content': 'Answer: B \nExplanation: This concept was expanded to replacement of posterior teeth by Livaditis. Perforated retainers were used to increase resistance and retention.', 'role': 'assistant'}]