Answer:
Option D, cutting the gene out of DNA with enzymes
Step-by-step explanation:
The first step in inserting a new gene into a bacterium is the separation of gene (to be inserted) from the parent cell DNA
Restriction enzyme (RE) is a DNA cutting enzyme which is used to cut this DNA. RE identifies a specific target sequence with in a DNA and then cut the DNA into two pieces either at or near the site.
For example - Human insulin gene is separated from the DNA of human and then inserted into plasmid of bacteria.