Which of the following best describes a nation-state?

any group in the world where the people in the government have a shared identity as a nation
a country that has well-defined borders and a government that is based on a shared common identity of all the people
a government that has been recognized by other countries or admitted to membership in the UN
a place where there are clear physical boundaries and a well-structured government run by the people

A country that has well-defined borders and a government that is based on a shared common identity of all the people

To determine which of the given options best describes a nation-state, we can break down and analyze each description:

1. "Any group in the world where the people in the government have a shared identity as a nation": This option suggests that a nation-state is any group where the people in the government share a national identity. While shared identity can be a characteristic of a nation-state, it alone does not encompass all the defining features.

2. "A country that has well-defined borders and a government that is based on a shared common identity of all the people": This option includes both well-defined borders and a government based on a shared common identity. A nation-state typically has these characteristics, as having clearly defined borders and a government that represents and governs its people based on their shared identity are important aspects.

3. "A government that has been recognized by other countries or admitted to membership in the UN": This option focuses on the recognition of a government by other countries or its inclusion in international organizations like the United Nations (UN). While international recognition can be an indicator of a nation-state, it is not the sole defining characteristic.

4. "A place where there are clear physical boundaries and a well-structured government run by the people": This option includes the presence of clear physical boundaries and a well-structured government that is controlled by the people. These elements are often associated with a nation-state, as having defined boundaries and a government run by the people are key defining features.

Based on the analysis, option 2, "a country that has well-defined borders and a government that is based on a shared common identity of all the people," best describes a nation-state, as it incorporates key elements that are usually present in such a political entity.

The second option, "a country that has well-defined borders and a government that is based on a shared common identity of all the people," best describes a nation-state. A nation-state is typically a sovereign state or country where the government and citizens share a common identity, such as language, culture, ethnicity, or history, and have well-defined territorial boundaries.