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': "'Stalactite' growth is a feature of the following organism: \nSelect and explain. \nA. Haemophilus, B. Pasteurella, C. Corynebacterium, D. Mycoplasma", 'role': 'user'}, {'content': "Answer: B \nExplanation: Stalactite' growth is a feature of Pasteurella pestis. If Pasteurella pestis (Yersinia pestis) grown in a flask or broth with oil or ghee (clarified butter) floated on top (ghee broth) a characteristic growth occurs which hangs down into the broth from the surface, resembling stalactites (stalactite growth). Ref: Textbook of Microbiology By Ananthanarayan And Paniker, 6th edition, Page 299.", 'role': 'assistant'}]