This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Growth, Subject name: Pediatrics
Delayed dentition is usually considered when there are no teeth by the age of? 
Select and explain. 
A. 18 months, B. 9 months, C. 16 months, D. 13 months
D: 13 months
Answer: D: 13 months 
Explanation: Delayed dentition is usually considered when there are no teeth has erupted by the age of 13 months Normally temporary teeth eruption is completed by 2 to 2.5yr of age