This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Bronchiectasis, Subject name: Medicine
[{'content': 'The most common cause of bronchiolitis is: \nSelect and explain. \nA. Respiratory syncytial virus, B. Adenovirus, C. Herpes virus, D. Influenza virus', 'role': 'user'}, {'content': 'Answer: A \nExplanation: M/C organism causing Bronchiolitis is RSV Other organisms are :- Influenza virus Parainfluenza virus Human metapneumovirus Coronavirus Adenovius Rhinovirus Palivizumab injection is used to prevent serious lung infection in children and babies caused by respiratory syncytial virus (RSV).', 'role': 'assistant'}]