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
Commonest presentation of infant with bilateral choanal atresia - 
Select and explain. 
A. Difficulty in breathing, B. Dysphagia, C. Smiling, D. Difficulty in walking
A: Difficulty in breathing
Answer: A: Difficulty in breathing 
Explanation: Bilateral choanal atresia presents as respiratory distress in newborn and requires support immediately after birth.