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
CHX mouthwash daily use till 2 week for streptococcus mutanus is effective for: 
Select and explain. 
A. 14-18 weeks, B. 12-14 weeks, C. 12-16 weeks, D. 12-26 weeks
D: 12-26 weeks
Answer: D: 12-26 weeks 
Explanation: None