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': 'Heel-raising movement of a RPD is prevented by: \nSelect and explain. \nA. Occlusal rests, B. Minor connector, C. Direct retainer, D. Indirect retainer', 'role': 'user'}, {'content': 'Answer: D \nExplanation: None', 'role': 'assistant'}]