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
Denominator age group for calculation of dependency ratio is 
Select and explain. 
A. 0-5 years, B. 5-15 years, C. 65 years and above, D. 15-65 years
D: 15-65 years
Answer: D: 15-65 years 
Explanation: None