The correct option is B Plasmids
Plasmids are employed in recombinant DNA technology. A plasmid is a small, extracellular DNA molecule that is physically separated from a chromosomal DNA and can replicate independently. It is used in recombinant DNA technology. Recombinant DNA (rDNA) molecules are DNA molecules formed by laboratory methods of genetic recombination to bring together genetic material from multiple sources, creating sequences that would not otherwise be found in biological organisms.