How can international migration influence a country's demographics?

International migration can significantly influence a country's demographics by introducing new populations that may alter age structures. When skilled workers migrate to a country, they often represent a younger demographic compared to the existing population. This influx of younger individuals can lead to an overall decrease in the average age of the population, which may be crucial for countering challenges associated with an aging population. A younger workforce is generally associated with higher fertility rates, productivity, and economic growth, all of which can help sustain social security systems and drive innovation.

The other options do not accurately capture the effects of international migration. The idea that migration typically has no demographic impact overlooks the profound changes that can occur in age distribution, ethnicity, and birth rates due to the movement of people. Claiming migration decreases diversity contradicts a fundamental outcome of migration, as it generally enriches the cultural fabric by introducing varied ethnicities, languages, and cultural practices. Lastly, the notion that migration isolates a country from global influences is misleading; international migration actually connects countries, facilitating cultural exchange and economic ties, rather than creating isolation.