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
Which of the following antibiotic is used in the treatment of Clostridium difficile associated diarrhoea? 
Select and explain. 
A. Ciprofloxacin, B. Metronidazole, C. Piperacillin, D. Clindamycin
B: Metronidazole
Answer: B: Metronidazole 
Explanation: Ans. is 'b' i.e. Metronidazole o Metronidazole is the DOC for clostrdium difficle associated diarrhoea. o Alternative drugs are vancomycin, fusidic acid, teicoplanin, and bacitracin.