Which of the following is a function of the Golgi apparatus?

The Golgi apparatus plays a crucial role in the post-translational modification, sorting, and packaging of proteins. One of its primary functions is to package proteins that are synthesized in the endoplasmic reticulum for secretion out of the cell. Once proteins arrive at the Golgi apparatus, they undergo further modifications, such as glycosylation, before being sorted and packaged into vesicles. These vesicles then transport the modified proteins to their destinations, which can include secretion outside the cell.

This role is essential for maintaining cell function, particularly in secretory cells that produce hormones or enzymes that need to be exported. The Golgi apparatus acts as a processing and shipping center within the cell, ensuring that proteins reach their correct locations, whether that is the cell membrane or the extracellular space.

The other functions listed in the question are characteristic of different cellular organelles. For example, mitochondria are responsible for ATP production, lysosomes contain hydrolytic enzymes for digestion, and the rough endoplasmic reticulum is the primary site of protein synthesis within the cell. The specificity of the Golgi apparatus in protein packaging highlights its vital function in cellular transport and communication.