This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Cell Wall Synthesis Inhibitors, Subject name: Pharmacology
[{'content': 'Imipenem is combined with cilastatin to \nSelect and explain. \nA. Cilastatin prevents degradation of imipenem in kidney, B. Cilastatin inreases intestinal absorption of imipenem, C. Cilastatin inhibits beta lactamase activity, D. Both have synergistic activity against Pseudomonas', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Imipenems rapidly inactivated by renal dehydropeptidase I, so it is combined with cilastatin, an inhibitor of this enzyme. Cilastatin, a reversible inhibitor of dehydropeptidase, increases the half life of imipenem and also inhibits the formation of nephrotoxic metabolite. Meropenem, doripenem and eapenemare not metabolized by renal dehydropeptidase', 'role': 'assistant'}]