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': 'Combination clasp consist of \nSelect and explain. \nA. Wrought wire reciprocal arm and cast retentive arm, B. Wrought retentive arm and cast reciprocal arm, C. Wrought reciprocal and wrought retentive arm, D. Cast retentive and cast reciprocal arm', 'role': 'user'}, {'content': 'Answer: B \nExplanation: None', 'role': 'assistant'}]