Answer: The correct answer for the fill in the blank is D) Nucleus, ribosomes.
In all eukaryotic cells, the process of transcription (formation of mRNA from DNA) takes place in the nucleus. mRNA (messenger RNA) is then transported to cytoplasm where it is translated to form proteins at the site called ribosomes.
Ribosome is a specialised membrane bound organelle that is responsible for assembly of proteins.
Thus, option D) Nucleus, ribosomes is the right answer.
