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: Microbiology
True statement about Pneumocystic Jiroveci is: 
Select and explain. 
A. Often associated with CMV infection, B. Usually diagnosed by sputum examination, C. Infection occurs only in immunocompromised patients, D. Always associated with Pneumatocele
B: Usually diagnosed by sputum examination
Answer: B: Usually diagnosed by sputum examination 
Explanation: Pneumocystis Jiroveci is usually diagnosed by sputum examination. Ref: Medical Microbiology By Jawetz, 24th Edition, Pages 648-49; Washington Manual of Pulmonary Medicine, 2006, Page 104; Pneumocystis Pneumonia By Walzer, Cushion, 3rd Edition, Page 418; Harrison's Principles of Internal Medicine, 16th Edition, Pages 1194-95