The correct option is B the genetic code is universal
In recombinant DNA technology, the recombinant DNA containing the gene of interest (even from human sources) are often transferred into host cells. The host cells include bacteria (prokaryotes) or yeast (eukaryotes) as they multiply rapidly to form huge populations to express the desired gene.
Expression of a gene product within a cell occurs through the process of transcription (transmission of information carried by DNA to RNA, mRNA molecule) and translation (synthesis of amino acid chain with the help of the genetic code carried by the mRNA).
Though the basic steps of transcription and translation in prokaryotes and eukaryotes are similar, they vary in several aspects. Still, the production of a human protein inside a bacteria, by genetic engineering, is possible if a functional gene having no introns is genetically engineered into a plasmid vector and transferred into a bacterial cell. The reason behind this is that the genetic code is nearly universal. With some minor exceptions, all living organisms (from bacteria to humans) use the same genetic code to synthesize proteins. The sequence of nucleotides in DNA that determines the sequence of amino acids in a polypeptide via an mRNA intermediate is known as genetic code.
Bacterial genome varies a lot from human genome with respect to length and composition. Bacterial genome is devoid of introns (non-coding regions) and hence bacteria do not have the apparatus for intron splicing. Also, the process of gene regulation varies a lot between prokaryotes and eukaryotes.