D) There are two major subunits, each with multiple proteins.
Explanation:
The ribosome is a complex structure made of RNA and proteins. Both prokaryotic and eukaryotic ribosomes have two subunits: small and large subunits. Each of these subunits is made of specific types of ribosomal RNAs (rRNA) and a number of different proteins.
For example, the 30S subunit of <em>E. coli</em> ribosome has 21 different proteins while its 50S subunit is made of 33 different types of proteins along with rRNA.
Likewise, the 40S subunit of a eukaryotic ribosome is made of 33 proteins while its 60S subunit has 47 proteins. The eukaryotic ribosome contains a total of 80 different proteins.
