Answer :
Population density is determined by the number of individuals of a species in a given area. This means that the correct answer is:
e. individuals of a species in a given area.
Population density is calculated by dividing the total number of individuals of a species in a specific area by the size of that area. For example, if there are 100 rabbits in a 10 square kilometer forest, the population density of rabbits in that forest would be 10 rabbits per square kilometer. This metric helps scientists understand how crowded or sparse a population is in a particular habitat.