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': 'Advantages of combination clasp: \nSelect and explain. \nA. It is flexible, B. It can be adjusted, C. It is more esthetic as compared to cast circumferential clasp, D. All of the above', 'role': 'user'}, {'content': 'Answer: D \nExplanation: None', 'role': 'assistant'}]