Answer:
The figure is absent in this question, however, it can be answered based on general understanding of the structure of rough endoplasmic reticulum. The options are:
A) Structure Y contributes the raw materials required for the synthesis of proteins
B) Structure Y packages proteins for export from the cell
C) Structure Y is the location where proteins are synthesized
D) Structure Y contains enzymes that cut and bind proteins.
The answer is C.
Step-by-step explanation:
The rough endoplasmic reticulum is one of the two types of the endoplasmic reticulum, which is a part of the endomembrane system found in eukaryotic cells. The rough endoplasmic reticulum is so named "rough" because of the structures attached to its surface.
The structures attached to the surface of the rough endoplasmic reticulum are the structures labelled Y in the figure of this question. Those structures are called RIBOSOMES and they are the site (organelles) of protein synthesis in living cells. Therefore, structure Y is the location where where proteins are synthesized.