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
Average gain of height in first year is ? 
Select and explain. 
A. 25 cm, B. 50 cm, C. 75 cm, D. 100cm
A: 25 cm
Answer: A: 25 cm 
Explanation: At birth, height is around 50 cm.
At one year, height is around 75 cm.
Thus gain in height in first year is 25 cm.