A nutritionist claims that replacing sugary drinks with water at school cafeterias reduces rates of childhood tooth decay.
Which finding, if true, would most strongly support the nutritionist's claim?
- A
Water is widely considered an essential nutrient.
- Bcheck_circle
After three school districts replaced sugary drinks with water, the average rate of new cavities in students dropped, while comparable districts that kept sugary drinks saw no change.
- C
Most children enjoy drinking sugary beverages.
- D
Some schools have offered both water and milk for decades.
Explanation
A provides a controlled comparison showing the predicted decline in cavities only where the policy was adopted. B, C, and D are tangential.