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
The most important mechanism by which gram negative bacilli acquire chloramphenicol resistance is : 
Select and explain. 
A. Decreased permeability into the bacterial cell, B. Acquisition of a plasmid encoded for chloramphenicol  acetyl transferase, C. Lowered affinity of the bacterial ribosome for chloramphenicol, D. Switching over from ribosomal to mitochondrial protein synthesis
B: Acquisition of a plasmid encoded for chloramphenicol  acetyl transferase
Answer: B: Acquisition of a plasmid encoded for chloramphenicol  acetyl transferase 
Explanation: None