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
The lag phase of tooth movement usually lasts for: 
Select and explain. 
A. 2-3 mins, B. 2-3 hrs, C. 2-3 day, D. 2-3 weeks
D: 2-3 weeks
Answer: D: 2-3 weeks 
Explanation: None