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: ENT
In a 5 year old child, most common cause of unilateral epistaxis is - 
Select and explain. 
A. Foreign body, B. Polyp, C. Atrophic rhinitis, D. Maggots
A: Foreign body
Answer: A: Foreign body 
Explanation: Most common cause of unilateral epistaxis in children is Foreign body.
In case of Foreign Body of Nose “The child presents with unilateral nasal discharge which is often foul smelling and occasionally blood-stained.”