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: Radiology
Cause for pneumatoceles 
Select and explain. 
A. Staph.aureus, B. P.carini, C. H.influenzae, D. All of the above
D: All of the above
Answer: D: All of the above 
Explanation: Pneumatoceles an thin - walled, gas - filled cystic lung spaces.
Causes :
S.aureus (infants & children).
P.carini (AIDS).
H.influenzae & E - coli (Neonate).