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 antibodies require dose adjustment in renal failure except? 
Select and explain. 
A. Ceftriaxone, B. Isoniazid, C. Erythromycin, D. Gentamicin
C: Erythromycin
Answer: C: Erythromycin 
Explanation: Rifampicin, Erythromycin, Doxycycline, Nafcillin, Cefoperazone are metabolized by liver and are safe in renal failure.