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': 'Which of the following is not true about hand instruments used in Operative Dentistry? \nSelect and explain. \nA. They are generally made of stainless steel, B. Nickel-Cobalt-chromium is never used in its fabrication, C. Carbon steel is more efficient than stainless steel, D. It can be made with stainless steel with carbide inserts', 'role': 'user'}, {'content': 'Answer: B \nExplanation: None', 'role': 'assistant'}]