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': "Reciprocal anchorage is offered by \nSelect and explain. \nA. Activator, B. Inter maxillary elastics, C. Maxillary expansion appliance, D. Catalan's appliance", 'role': 'user'}, {'content': 'Answer: C \nExplanation: None', 'role': 'assistant'}]