The correct option is B 2
Ribosomes are made up of two subunits. Depending upon their rate of sedimentation, there are two types of ribosomes as 70S and 80S. 70S type of ribosome is present in prokaryotes and it possesses two subunits as 30S and 50S. 80S type of ribosome is present in eukaryotes and it possesses two subunits as 60S and 40S.