The correct answer is: a) GDP per capita.
GDP per capita is a measure of the economic output of a country divided by its population. It is often used as a proxy for the standard of living, as it reflects the average amount of goods and services that each person in a country consumes.
Income inequality is a measure of the distribution of income within a country. It is often measured by the Gini coefficient, which ranges from 0 to 1, with 0 representing perfect equality and 1 representing perfect inequality. Income inequality can be a problem because it can lead to social unrest and political instability.
Access to basic amenities is a measure of the availability of basic services such as clean water, sanitation, electricity, and education. It is often used as a proxy for the quality of life, as it reflects the extent to which people have access to the resources they need to live a healthy and productive life.
Consumer spending is a measure of the total amount of money that people in a country spend on goods and services. It is often used as a proxy for economic growth, as it reflects the level of demand for goods and services in the economy.
GDP per capita is the most commonly used measure of the standard of living because it is a relatively simple and straightforward measure. It is also a good measure of the overall size of the economy, which can be important for understanding a country’s economic potential. However, GDP per capita does not take into account the distribution of income, so it can be misleading if used to compare the standard of living of different countries.