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: Unknown
[{'content': 'Burkholderia cepacian is intrinsically resistant to: \nSelect and explain. \nA. Ciprofloxacin, B. Ceftiaxone, C. Polymyxin B, D. Ampicillin', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Ref. Robbins Pathology. 9th edition. Page. 300\n\xa0\nBurkholderia. Features: \n\nGram-negative opportunists found in moist environments like Pseudomonas. \u2028\nCase infections in people with cystic fibrosis and immunocompromised patients \u2028(Burkholderia cepacia complex). \u2028\nThese are intrinsically resistant to PolyMyxin B\nBurkholderia pseudomallei causes melioidosis, an infectious disease endemic in \u2028Southeast Asia; it also causes localized infection as well as systemic (e.g., not just \u2028pneumonia).', 'role': 'assistant'}]