Final answer:
The population decline in the late 20th century was caused by factors such as falling birth rates in industrialized nations, migration due to wars and natural disasters, and colonization and exploitation by European powers.
Step-by-step explanation:
The population decline in the late 20th century can be attributed to various factors. One major cause was the reduction in family size caused by falling birth rates in industrialized nations. This phenomenon, known as the demographic transition, resulted from factors such as improved access to contraception, increased focus on education and careers, and changing societal norms.
Another contributing factor was migration, with large numbers of people being displaced due to wars, political upheavals, and natural disasters. These events drove people from their homes in different regions around the world.
Furthermore, factors like colonization and exploitation by European powers had a significant impact on population decline. These powers depleted local environments and resources, leading to violence against indigenous populations who resisted these economic conditions.
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