The best answer is B.
Once a genetically engineered plasmid has been inserted in bacteria, the bacteria will begin making proteins from the inserted modified genes as it goes about making proteins from its own chromosomal DNA.
The plasmid for example may have genes that code for production of enzymes that can inactivate antibiotics. Once the plasmid has been inserted into a new bacteria that previously could not inactivate antibiotics, the new bacteria begins to make the enzyme responsible for this all in the process of making other protein products from its own Chromosomal DNA.
