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': 'Most common catheter-related bloodstream infection is - \nSelect and explain. \nA. Candida, B. Gram negative organisms, C. Coagulase positive staphylococci, D. Coagulase negative staphylococci', 'role': 'user'}, {'content': 'Answer: D \nExplanation: "The most common pathogens isolated from vascular device-associated bacteremia include coagulase-negative\xa0staphylococci, S. aureus, enterococci, nosocomial gram-negative bacilli and candida."\n"Staph aureus is second only to CoNS as a cause of primary nosocomial bacteremia" \nSo:\n\nM.C. cause of catheter-related bloodstream infection → coagulase-negative staphylococci\n2nd MC cause of catheter-related bloodstream infection → coagulase-positive staphylococci (S. aureus)', 'role': 'assistant'}]