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': 'Focus group discussion should have \nSelect and explain. \nA. 4 - 6 members, B. 6 - 12 members, C. > 12 members, D. < 4 members', 'role': 'user'}, {'content': 'Answer: B \nExplanation: None', 'role': 'assistant'}]