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
Burkholderia cepacian is intrinsically resistant to: 
Select and explain. 
A. Ciprofloxacin, B. Ceftiaxone, C. Polymyxin B, D. Ampicillin
C: Polymyxin B
Answer: C: Polymyxin B 
Explanation: Ref. Robbins Pathology. 9th edition. Page. 300
 
Burkholderia. Features: 

Gram-negative opportunists found in moist environments like Pseudomonas.  
Case infections in people with cystic fibrosis and immunocompromised patients  (Burkholderia cepacia complex).  
These are intrinsically resistant to PolyMyxin B
Burkholderia pseudomallei causes melioidosis, an infectious disease endemic in  Southeast Asia; it also causes localized infection as well as systemic (e.g., not just  pneumonia).