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: Dental
Which of the following is one of the objectives of “Oral Global Health by 2000 AD”? 
Select and explain. 
A. Complete eradication of dental caries, B. Zero DMF incidence at age 12, C. 50% of the 5-6 years old should be caries free, D. Incidence of DMFS not more than 2-3 at age 12
C: 50% of the 5-6 years old should be caries free
Answer: C: 50% of the 5-6 years old should be caries free 
Explanation: Objective of WHO Oral Global Health by 2000:

50% of the 5-6 years old should be caries free.
Global average should be no more than 3 DMF at age 12. 
 85% of population should retain all their teeth by age 18.
A 50% reduction in edentulousness in present levels at age 35-40 years should be achieved.  
A 25% reduction in present level of edentulous at age 65 or more.
A data-based system for monitoring changes in oral health should be established.

World Health Organisation
https://www.who.int/oral_health/publications/goals2020/en/