Correct Answer: D
Explanation:
Restriction enzymes do not attack the bacterium itself because its DNA has been chemically modified in a way that immunizes it.
Restriction enzymes, also known as restriction endonucleases, are enzymes that cut a DNA molecule at a particular place. They are essential tools for recombinant DNA technology. The enzyme "scans" a DNA molecule, looking for a particular sequence, usually of four to six nucleotides.