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': 'An expansion alliance made with an expansion screw is an example of: \nSelect and explain. \nA. Simple anchorage, B. Reciprocal anchorage, C. Multiple anchorage, D. Reinforced anchorage', 'role': 'user'}, {'content': 'Answer: B \nExplanation: None', 'role': 'assistant'}]