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': 'In measuring Vickers hardness no. which of the following is used: \nSelect and explain. \nA. Spherical indenter, B. Steel ball indentation, C. Rhomboid shaped indenter, D. 136-degree diamond pyramid', 'role': 'user'}, {'content': 'Answer: D \nExplanation: None', 'role': 'assistant'}]