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': 'Beta titanium, an excellent choice for auxiliary springs is nothing but: \nSelect and explain. \nA. Nitinol, B. TMA, C. Stainless steel, D. Sentinol', 'role': 'user'}, {'content': 'Answer: B \nExplanation: None', 'role': 'assistant'}]