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
Extended-spectrum beta-lactamases (ESBLs) are characterized by activity against all except : 
Select and explain. 
A. Penicillinases, B. Cephalosporinases, C. Oxyimino–cephalosporinases, D. Carbapenems
D: Carbapenems
Answer: D: Carbapenems 
Explanation: Carbapenems like imipenem are the only beta-lactams reliably efficacious against ESBL producing bacteria.