Which of the following is a possible explanation of a eukaryotic gene which fails to produce a functional protein when incorporated into a bacterial chromosome? 

In bacteria the codons may encode for different amino acids than in eukaryotes.

The eukaryotic gene may contain introns, which are non-coding regions of DNA that interrupt the coding sequence while Bacteria do not have the machinery to process introns.

The eukaryotic gene may require post-translational modifications, such as glycosylation or phosphorylation, that cannot be performed by bacterial enzymes.

The gene may be regulated by eukaryotic-specific transcription factors or regulatory elements that are not present in bacteria.

All of the above.

none of the above.