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': 'Demographic process includes \nSelect and explain. \nA. Morbidity, B. Marriage, C. Family planning, D. Education', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Demographic process work on\n\nMarriage.\nFertility.\nMortality.\nMigration.\nSocial mobility.', 'role': 'assistant'}]