Final answer:
The Human Development Index is based on three essential elements: a long and healthy life, the ability to acquire knowledge, and the means to secure a decent standard of living, which aligns with answer option C.
Step-by-step explanation:
The Human Development Index (HDI) probes into the essence of human potential and achievement. The three essential elements of human life which the HDI is based upon are: a long and healthy life, the ability to acquire knowledge, and access to resources needed for a decent standard of living. Therefore, the correct answer to the student's question is C. A long and healthy life, the ability to acquire knowledge, and access to resources needed for a decent standard of living.
A long and healthy life is determined by life expectancy at birth. The ability to acquire knowledge is assessed by mean years of schooling for adults and expected years of schooling for children. Resources needed for a decent standard of living are calculated using Gross National Income (GNI) per capita, adjusted for purchasing power parity (PPP).
This comprehensive approach was envisaged by Pakistani economist Mahbub ul Haq and has been developed further by incorporating elements like the Gender Development Index (GDI) and the Inequality-adjusted Human Development Index (IHDI), allowing for more nuanced understanding of inequalities within societies.