Concept:Population density is the number of people living in one unit area of land.
Explanation:It is found by dividing the total population of a region by its total land area.
The result is usually given as the number of people per square kilometre.
For example, if a region has
800,000 people and an area of
400km2, its population density is
2000 people per square kilometre.
This measurement shows how crowded or sparsely populated an area is.
Birth rate is the number of live births per
1000 people in a year.
Death rate is the number of deaths per
1000 people in a year.
Dependency ratio compares the dependent population with the working-age population.
None of these terms involves land area, so they do not match the definition given in the question.
Answer:D. Population density