Which statement describes the role of Ribosomes?

Ribosomes play a crucial role in the process of protein synthesis, which is fundamental to cellular function. They are the molecular machines that facilitate the translation of messenger RNA (mRNA) into polypeptide chains, which then fold into functional proteins. Ribosomes can be found floating freely in the cytoplasm or attached to the endoplasmic reticulum, often called the rough ER due to the presence of these ribosomes. The primary function of ribosomes is to read the genetic instructions carried by the mRNA and assemble the corresponding amino acids in the correct sequence to form proteins. This process is essential for various cellular activities, growth, and repair.

The other options relate to different cellular functions. For instance, cell division is primarily managed by various other cellular structures, including the mitotic spindle and centrosomes. Hormone synthesis generally involves glands and specific cell types, and while ribosomes are involved in producing proteins that can function as hormones, they do not synthesize hormones directly. Energy generation is primarily the responsibility of mitochondria and certain cellular processes rather than ribosomes. Therefore, the statement that ribosomes build proteins accurately reflects their primary and defining role in the cell.