This subcellular structure functions to modify gene expression products before they are shuttled out of the cell via exocytosis.

The correct answer will be- Golgi apparatus

Explanation:

The proteins are synthesized in the ribosomes whether they are attached to the endoplasmic reticulum or free. These synthesized proteins enter the lumen of the endoplasmic reticulum where they get packaged to go to Golgi apparatus.

The Golgi apparatus is the site of post-translational modification of the secreted proteins like ubiquitination, acetylation, phosphorylation and many others.

Thus, the Golgi apparatus is the correct answer.

life would be meaningless without memes