The correct option is B Microinjection
With the advancment in the technology, new methods of transferring genes into organisms have been invented. Gene gun is a new tool to introduce the gene into the cell. An elemental particle of a heavy metal is the payload to which the DNA is attached! Gene gun is motly used for plant species. Another technique for vectroless gene transfer is microinjection. The genes are directly injected into the nucleus. This is mostly done to oocytes.