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': '"Malta" fever is caused by: \nSelect and explain. \nA. Treponema, B. Borellia, C. Brucella, D. Pseudomonas', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Brucella', 'role': 'assistant'}]