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: Surgery
[{'content': 'Best skin disinfectant for central line insertion is: \nSelect and explain. \nA. Povione iodine, B. Alcohol, C. Cetrimide, D. Chlorhexidine', 'role': 'user'}, {'content': 'Answer: D \nExplanation: "Chlorhexidine is now the disinfectant recommended for all catheter placement procedures and for routine site cleansing during dressing changes."- Comprehensive Hospital Medicine: An Evidence-Based And Systems Approach By Mark V. Williams, Scott A. Flanders, p320\n"Use of antiseptic solution for skin disinfection at the catheter insertion site helps prevent catheter-related infection. \nChlorhexidine-based solutions appear to be superior to both aqueous and alcohol-based povidone-iodine in reducing the risk for catheter colonization and catheter-related bloodstream infection. If there is a contraindication to chlorhexidine, tincture of iodine, an iodophor or 70 per cent alcohol can be used as alternatives"-uptodate.com', 'role': 'assistant'}]