Answer: c. protein synthesis.
Step-by-step explanation:
Ribosomes are small particles (12nm wide and 25nm long) composed of proteins and rRNA. Each ribosome is composed of a larger subunit and a smaller subunit with sedimentation values of 60S and 40S, respectively. Ribosomes are responsible for protein synthesis. Ribosomes are free in the cytoplasm when they synthesize cytosol, nucleus, mitochondria, and peroxisome proteins. They associate with an mRNA ribbon, forming groups in the form of circles, spirals or rosettes, called polysomes or polyribosomes.