The correct option is A Bioreactor / fermenter
Bioreactor or Fermenter is an apparatus in which a biological reaction or process is carried out, especially on an industrial scale. In Recombinant DNA technology, the product is usally obtained by transfering the gene into a fast growing organisms such as E.coli. Fermenters can grow several liters of E.coli in broth, which ends up giving high yield of the gene product.