The correct option is D All of the above
The antibiotic is the chemical substance produced by microorganisms can kill or inhibit the growth of the other microorganisms and thus used to treat bacterial and fungal infections. But some bacteria have developed resistance to antibiotics by (1) enzymatic degradation of antibacterial drugs, (2) alteration of bacterial proteins that are antimicrobial targets, (3) changes in membrane permeability to antibiotics, (4) by a genetic mutation, (5) by acquiring resistance from another bacterium, (6) slime layer to protect the bacteria cells from environmental dangers such as antibiotics and desiccation. Antibiotic resistance can be either plasmid-mediated or maintained on the bacterial chromosome. Thus, the correct answer is option D.