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: Medicine
[{'content': 'Most common catheter induced blood infection is due to - \nSelect and explain. \nA. Staphylococcus aureus, B. Coagulase negative staphylococci, C. Gram negative bacilli, D. Candida', 'role': 'user'}, {'content': 'Answer: B \nExplanation: None', 'role': 'assistant'}]