Biology

The correct answer is D.nucleolus.

The nucleolus is the region within the nucleus of a cell where ribosomal RNA (rRNA) is synthesized and combined with proteins to form the subunits of ribosomes. These ribosomal subunits are then transported out of the nucleus into the cytoplasm where they combine to form functional ribosomes, which are essential for protein synthesis.

Here is a brief explanation of each option:

A.Nuclear membrane: A double membrane structure that surrounds the nucleus, protecting its contents and regulating...