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: Social & Preventive Medicine
[{'content': 'All of following comes under random sampling method except \nSelect and explain. \nA. Simple random sampling, B. Quota sampling, C. Stratified sampling, D. Cluster sampling', 'role': 'user'}, {'content': 'Answer: B \nExplanation: None', 'role': 'assistant'}]