This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Prevention of Surgical Infections, Subject name: Surgery
Best skin disinfectant for central line insertion - 
Select and explain. 
A. Povidone iodine, B. Alcohol, C. Chlorhexidine, D. Cetrimide
C: Chlorhexidine
Answer: C: Chlorhexidine 
Explanation: Ans. is 'c' i.e., Chlorhexidine o "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, p320o "Use of antiseptic solution for skin disinfection at the catheter insertion site helps prevent catheter-related infection. Chlorhexidine-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 percent alcohol can be used as alternatives "-uptodate.com