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': 'Positive mortality indicator is - \nSelect and explain. \nA. IMR, B. Child mortality rate, C. MMR, D. Life expectancy', 'role': 'user'}, {'content': 'Answer: D \nExplanation: Mortality indicators\nThese are\n\nCrude death rate\nExpectation of life (life expectancy)\nInfant mortality\xa0rate\nChild mortality rate\nUnder-5 proportional mortality\xa0rate\nMaternal mortality rate\nDisease specific mortality\xa0rate\nAge specific death rate\nAdult mortality rate\nYears of potential life lost\n\n\nAmong these only life expectancy is a posive mortality indicator, i.e. increase life expectancy means improvement in health.\nAll other are ‘negave’ health indicators, i.e. increase value of these indicators implies poor health of community.', 'role': 'assistant'}]