This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Infectious Lung Disease: Pneumonia, Subject name: Pathology
Masson bodies are seen in: 
Select and explain. 
A. Usual interstitial pneumonia, B. Non-specific interstitial pneumonia, C. Cryptogenic Organizing Pneumonia, D. Hyaline membrane disease
C: Cryptogenic Organizing Pneumonia
Answer: C: Cryptogenic Organizing Pneumonia 
Explanation: Masson bodies is characterized by involvement of alveolar space. Alveolar space & bronchioles have collection of Fibroblast. It is seen in patient with Cryptogenic Organizing Pneumonia. Cryptogenic organizing pneumonia aka bronchiolitis obliterans organizing pneumonia. Usual interstitial pneumonia - associated with Idiopathic pulmonary fibrosis .