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': 'A family where all its members are playing a part in management \nSelect and explain. \nA. Communal family, B. Problem family, C. Nuclear family, D. Joint family', 'role': 'user'}, {'content': 'Answer: A \nExplanation: None', 'role': 'assistant'}]