The correct answer is in-migration.
In-migration is the movement of people into a country or region. It is the opposite of out-migration, which is the movement of people out of a country or region. Emigration is the movement of people out of their country of origin, while immigration is the movement of people into a country other than their country of origin.
In-migration can be caused by a number of factors, including economic opportunities, political instability, and natural disasters. It can also be caused by social factors, such as family reunification or marriage.
In-migration can have a number of positive and negative effects on a country or region. On the positive side, it can lead to an increase in the workforce, which can boost economic growth. It can also lead to an increase in diversity, which can enrich the cultural life of a country or region.
On the negative side, in-migration can lead to an increase in competition for jobs and housing. It can also lead to social tensions, as new arrivals may have different customs and values than the native population.
Overall, in-migration is a complex issue with both positive and negative effects. It is important to weigh the costs and benefits of in-migration before making any decisions about whether or not to encourage it.