After the DNA is translated by the RNA polymerase and the mRNA strand is synthesized, the next step is to synthesize the proteins. For this, the mRNA must exit the nucleus and migrate to the endoplasmatic reticulum, where the ribosomes attached to the membrane of the endoplasmatic reticulum help the tRNA read the sequence of the mRNA so that the correct amino acids can be attached to make the protein.
The correct option is D.