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
If fluoride concentration of community water is___________ppm, no need of any flouride supplement at any stage. 
Select and explain. 
A. >1 ppm, B. >0.7 ppm, C. >2 ppm, D. >1.5 ppm
B: >0.7 ppm
Answer: B: >0.7 ppm 
Explanation: Supplemental fluoride depends on the age of child and F- level in water.
Below 4 years, fluoridated dentifrices are not recommended
Below 2 years, F- tablets are not recommended.
Below 6 years, F- mouthwash is not recommended.
If F- concentration of community water is >0.7 ppm, no need of any F- supplement at any age.

Essentials of preventive and community dentistry 
Soben Peter 
5th edition