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: Pharmacology
The combination of trimethoprim and sulfamethoxazole is effective against which of the following opportunistic infections in the AIDS patient? 
Select and explain. 
A. Disseminated Herpes simplex, B. Cryptococcal meningitis, C. Pneumocystis jirovecii, D. Tuberculosis
C: Pneumocystis jirovecii
Answer: C: Pneumocystis jirovecii 
Explanation: None