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
When do we have to sta antibiotics to prevent post-operative infection? 
Select and explain. 
A. 2 days before surgery, B. After surgery, C. 1 week before surgery, D. 1 hour before surgery & continue after surgery
D: 1 hour before surgery & continue after surgery
Answer: D: 1 hour before surgery & continue after surgery 
Explanation: Ans. is 'd' i.e., 1 hour before surgery & continue after surgery Prophylactic antibiotics are administered before the skin incision is made. Repeat dosing occurs at an appropriate interval, usually 3 hours for abdominal cases or twice the half-life of the antibiotic. Perioperative antibiotic prophylaxis generally is not continued beyond the day of surgery.