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': 'The best sampling procedure that can be followed is \nSelect and explain. \nA. Simple random, B. Stratified random, C. convenient, D. Systematic', 'role': 'user'}, {'content': 'Answer: B \nExplanation: None', 'role': 'assistant'}]