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
Surgical wound of trans-alveolar extraction mostly falls under which of these categories? 
Select and explain. 
A. Clean, B. Clean-contaminated, C. Dirty-infected, D. None of the above
B: Clean-contaminated
Answer: B: Clean-contaminated 
Explanation: Most of these procedures fall under clean-contaminated or contaminated categories.