The correct answer is Education.
The Human Development Index (HDI) is a composite statistic of life expectancy, education, and per capita income indicators, which are used to rank countries into four tiers of human development. The HDI is used to measure a country’s achievements in terms of longevity, education, and standard of living.
Education is one of the three pillars of the HDI, along with life expectancy and per capita income. Education is important for human development because it helps people develop their skills and knowledge, which can lead to better jobs and higher incomes. Education also helps people understand their rights and responsibilities, and it can promote social cohesion and tolerance.
The adult literacy rate is a measure of the percentage of adults in a country who can read and write. The adult literacy rate is an important indicator of education because it shows the level of educational attainment in a country. A high adult literacy rate indicates that a country has a well-educated population, which can lead to economic growth and development.
The other options are not as important for human development as education. Income is important, but it is not the only factor that determines a person’s well-being. Health is also important, but it is not the only factor that determines a person’s quality of life. Standard of living is a measure of a person’s material possessions, but it is not the only factor that determines a person’s happiness.