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: Pharmacology
Which of the following cephalosporin is not active against anaerobes: 
Select and explain. 
A. Cefoperazone, B. Cefotetan, C. Cefmetazole, D. Cefoxitin
A: Cefoperazone
Answer: A: Cefoperazone 
Explanation: None