What do we call the process by which a person becomes a citizen?

The process by which a person becomes a citizen is known as naturalization. This legal procedure involves fulfilling certain requirements set by a country, such as residing there for a specific period, demonstrating knowledge of the country’s history and government, and showing proficiency in the language. Once a person completes these requirements and is approved, they are granted citizenship, which confers rights and responsibilities associated with being a member of that nation.

In contrast, immigration refers to the act of moving to another country to live there permanently or for a long period, but it does not inherently confer citizenship. Natural selection is a biological concept relating to evolution and has no connection to citizenship. Citizenship itself is the status of being a legal member of a state; the term does not specify the process by which that status is acquired. Hence, naturalization is the correct term that specifically describes the path to becoming a citizen.