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': 'Cutting edges of the orthodontic instruments are made up of \nSelect and explain. \nA. Austenitic carbon steel, B. Martensitic carbon steel, C. Ferritic carbon steel, D. Cementite carbon steel', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Because of their high yield strength and hardness, martensitic stainless steels are used for surgical and cutting instruments.\xa0\nThe austenitic stainless steels are the most corrosion-resistant of the three major types and are the stainless steels used for orthodontic wires, endodontic instruments, and crowns in pediatric dentistry.\nFerritic Stainless Steels: These alloys provide good corrosion resistance at a low cost, when high strength is not required. They cannot be hardened by heat treatment or readily work-hardened. Consequently, they have little application in dentistry.\nRef: Phillip’s 12th edition page 406', 'role': 'assistant'}]