A universal genetic code allows for which of the following?

A gene from one species is successfully inserted into another species genome

. All organisms to have the same number of genes in their nuclear chromosomes. The processes of transcription and translation to produce the same proteins in all species.

Descendants of the same common ancestor all have the same chromosomes in their nuclei.

A universal genetic code allows scientists to take a gene from one species and successfully insert it into another. It is virtually universal due to all life originating from the same single celled ancestor

A universal genetic code allows "the processes of transcription and translation to produce the same proteins in all species."

To say that the genetic code is universal it means that it is read/interpreted in the same exact way in all cells. This is that the same group of three nucleotides, a codon, will always translate into the same amino acid in any cell leading to the formation of the same protein, or at least a protein with same amino acids when first formed.