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': 'Nickel-Titanium alloy has \nSelect and explain. \nA. unreliable spring back, B. low spring back, C. minimal spring back, D. none of the above', 'role': 'user'}, {'content': 'Answer: D \nExplanation: None', 'role': 'assistant'}]