This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Growth and development, Subject name: Pediatrics
Delayed dentition is seen in ____________ 
Select and explain. 
A. Down syndrome, B. Congenital hypothyroidism, C. Rickets, D. All of the above
D: All of the above
Answer: D: All of the above 
Explanation: .Abnormalities in tooth eruption (timing and sequence) is often caused by genetics and may result in malocclusion. In severe cases, such as in Down syndrome,congenital hypothyroidism & rickets , the eruption may be delayed by several years and some teeth may never erupt Reference: GHAI Essential pediatrics, 8th