What is the biological version of the theory that states that formal education insulate people from the effects of neurocognitive disorder due to alzheimer's disease?

Many organizations release indexes used to measure the development of the world's countries. as we learned in this lesson, these indexes measure many factors, from life expectancy to happiness. in your opinion, what are the three most important factors we can use to determine how developed a country might be? explain your answers in a few sentences.