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
[{'content': 'Metronidazole is effective in all of the following conditions except - \nSelect and explain. \nA. Pseudomembranous colitis, B. Neurocysticercosis, C. Giardiasis, D. Amebic liver abscess', 'role': 'user'}, {'content': "Answer: B \nExplanation: Ans. is 'b' i.e., Neurocysticercosis", 'role': 'assistant'}]