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 efficiency is best with which of the following materials? \nSelect and explain. \nA. Carbide, B. Stainless steel, C. Carbon steel, D. Cobalt-chromium alloys', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Hand instrument are made of stainless steel, carbon steel, or blades of tungsten carbide soldered to a steel handle. Carbon steel is able to keep a cutting edge better than stainless steel.\nCarbide blades, however, are the most efficient in cutting, even though they are somewhat brittle.\nRef: Operative dentistry modern theory and practice Marzouk page 59', 'role': 'assistant'}]