This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Respiratory System, Subject name: Pediatrics
An 11-month-old child presents with complaints of respiratory distress. On examination there is bilateral crepitation and wheezing. Which of the following is the most likely cause? 
Select and explain. 
A. Pneumonia, B. Adenovirus, C. RSV, D. Rhinovirus
C: RSV
Answer: C: RSV 
Explanation: c. RSV(Ref: Nelson's 20/e p 2044-2047, Ghai 8/e p 381-382)The clinical features are suggestive of Acute Bronchiolitis, for which the most common causative agent is RSV.