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: Pediatrics
A child's growth variation is normal but bone development is not acc to the chronological age.What is diagnosis ? 
Select and explain. 
A. Genetic, B. Dwarfism, C. Constitutional delay, D. Familial short stature
C: Constitutional delay
Answer: C: Constitutional delay 
Explanation: The child in this question has :


Height below 3rd percentile, i.e., short stature.
Normal growth velocity, i.e., a normal variant of short stature.
Skeletal age is less than chronological age.


There are two types of a normal variant of short stature.


Constitutional delay in growth
Familial genetic short stature


In constitutional delay, the bone age is less than chronological age, while in familial short stature bone age is normal for the chronological age.
So, the most likely diagnosis of this child is a constitutional delay in growth.