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
Positive indicator of health ? 
Select and explain. 
A. IMR, B. Child moality rate, C. MMR, D. Life expectancy
D: Life expectancy
Answer: D: Life expectancy 
Explanation: Ans. is 'd' i.e., Life expectancy