This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Respiration, Subject name: Pathology
A full term neonate rapidly develops progressive respiratory distress shortly after birth, lung biopsy done post-mortem reveals the following, what is your diagnosis? 
Select and explain. 
A. Pulmonary hemorrhage, B. Pulmonary alveolar proteinosis, C. Pneumonia, D. Pulmonary edema
B: Pulmonary alveolar proteinosis
Answer: B: Pulmonary alveolar proteinosis 
Explanation: Ans. (b) Pulmonary alveolar proteinosisThe alveoli are filled with a dense, amorphous, protein-lipid granular precipitate, while the alveolar walls are normal.