Which two components make up the population growth rate?

• A. Birth rate and death rate
• B. Net migration rate and natural increase rate
• C. Immigration rate and emigration rate
• D. Ground water and pollution levels

Answer: (B)

Population growth rate comes from two pieces: natural increase and net migration. Natural increase is births minus deaths, showing how the population would change if people were only staying in place. Net migration is immigration minus emigration, showing how many people are added or lost because of people moving across borders. Add those two together and you get the total change in population over a period.

So, the two components that make up the population growth rate are the natural increase rate and the net migration rate. For example, a country might have births exceeding deaths by a small amount (positive natural increase) and also attract more people from abroad than it loses (positive net migration); combined, that leads to a larger overall growth rate. Immigration and emigration together form net migration, not the growth rate by themselves, and environmental factors like groundwater or pollution levels don’t determine population size.