This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Nose and paranasal sinuses, Subject name: ENT
M/c causes of epistaxis in 3years old child: 
Select and explain. 
A. Nasal polyp, B. Foreign body, C. Upper respiratory catarrh, D. Atrophic rhinitis
C: Upper respiratory catarrh
Answer: C: Upper respiratory catarrh 
Explanation: M/C cause of epistaxis in children is idiopathic 2nd most common of epistaxix in children is: infection/trauma-development of crusts-nasal picking/digital trauma-nasal bleed. Ref.Scott Brown 7/e,vol 1,p 1064.