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: Pediatrics
A girl child with fever, cough, dyspnoea with x–ray showing right lower lobe patchy consolidation, for which treatment was given. After 8 weeks symptom improved but x-ray showed more dense consolidation involving the whole of the right lower lobe. What is the next best line of investigation ? 
Select and explain. 
A. Bronchoscopy, B. Culture from nasopharynx, C. Barium esophagogram, D. Allergic skin test
A: Bronchoscopy
Answer: A: Bronchoscopy 
Explanation: A history of recurrent pneumonia in the same lobe or segment or slow resolution (> 3 months) of pneumonia on successive radiographs suggests the possibility of bronchial obstruction and the need for bronchoscopy.