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
Metronidazole is LEAST likely to be effective in the treatment of : 
Select and explain. 
A. Hepatic amoebiasis, B. Infection caused by Bacteroides fragilis, C. Pseudomembranous colitis, D. Pneumocystosis
D: Pneumocystosis
Answer: D: Pneumocystosis 
Explanation: None