This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Protein Synthesis Inhibitors, Subject name: Pharmacology
All of the following organisms are susceptible to Amikacin except: 
Select and explain. 
A. Pseudomonas, B. Serratia, C. Proteus, D. Enterococci
D: Enterococci
Answer: D: Enterococci 
Explanation: Amikacin : Its active against many Gram negative bacteria, including many strains of Proteus, Pseudomonas, Enterobacter, and Serratia. It also active against M.Tb and also Streptomycin resistant strains. However it is not active against Enterococci and Gram positive bacteria. So it should not be used against these.