Sagot :
Answer: B) Population size is the total number of organisms, while population density is the total number of organisms within a given area.
Population size refers to the total number of organisms present in a  population. On the other hand, population density reflects population size per unit area.
For example- In a population, if 200 individuals are living in 100 square meter of area.
Population size = 200
Population density = 200/ 100 = 2 individuals per square meter.