When considering developed nations and less-developed nations, one should remember that "development" refers to?

When considering developed nations and less-developed nations, one should remember that "development" refers to a nation's ability to feed, cloth, and shelter its people.
The primary measure of a country's development is per capital gross domestic product.Factors like lifespan, energy consumption, per capital value, skill rates, and infant mortality rate are used to measure a country's development. 

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