Final answer:
Emigration is the movement of people out of a population, which decreases its size and can alter growth rates. It is an aspect of migration, a broader term encompassing various types of human movement including immigration, internal migration, and seasonal migration.
Step-by-step explanation:
The correct definition for emigration is the movement of individuals out of a population. This process can decrease the population size and affect the growth rate of the place they are leaving. An equation for calculating population growth considering migration factors would be: growth rate = (birth rate + immigration rate) – (death rate + emigration rate).
Migration as a broader term includes both immigration, which is the movement into a location, and emigration, the movement out of a location. Migration can be influenced by various reasons, such as seeking employment, pursuing education, evading political instability or conflict, environmental conditions, or simply for personal or familial reasons.
Emigration is one among several types of migration, such as internal migration, external migration, return migration, and seasonal migration, reflecting the complex nature of human movement.