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 ugly duckling stage is seen at the age of 
Select and explain. 
A. 6 - 7 years, B. 9 -10 years, C. 10 - 12 years, D. 12 - 14 years
B: 9 -10 years
Answer: B: 9 -10 years 
Explanation: None