This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Chemotherapy, Subject name: Pharmacology
Which is not a beta lactum antibiotic? 
Select and explain. 
A. Penicillin, B. Carbepenem, C. Monobactum, D. Azithromycin
D: Azithromycin
Answer: D: Azithromycin 
Explanation: These are antibiotics having a beta-lactam ring. The two major groups are penicillins and cephalosporins. Monobactams and carbapenems are relatively newer additions. ESSENTIALS OF MEDICAL PHARMACOLOGY page no.716