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
[{'content': 'Actinomyces differs from bacteria in that: \nSelect and explain. \nA. Gram positive, B. Filamentous organism, C. Non-motile, D. Non-acid fast', 'role': 'user'}, {'content': "Answer: B \nExplanation: Ans. is. 'b' i. e. Filamentous organism", 'role': 'assistant'}]