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
All of the following cephalosporins have a good activity against pseudomonas aeruginosa EXCEPT: March 2003 
Select and explain. 
A. Cephadroxil, B. Cefipime, C. Cefoperazone, D. Ceftazidime
A: Cephadroxil
Answer: A: Cephadroxil 
Explanation: Ans. A i.e. Cephadroxil