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
Effective use of dental floss can be expected to: 
Select and explain. 
A. Significantly reduce caries activity, B. Improve gingival health, C. Restrict plaque development, D. Effectively alter the oral environment
B: Improve gingival health
Answer: B: Improve gingival health 
Explanation: None