HDI is entrusted with reference to:
I. Life expectancy at birth
II. Real GDP / per capita
III. Infant mortality
IV. Morbidity
The full form for HDI is Human Development Index. Many components have been added by the Human Development Report in the calculation of the Human Development Index. These components show that the development could be assessed only by knowing what is happening to the citizens of the country. These include life expectancy at birth, Real GDP/ per capita, infant mortality morbidity and other factors.
Thus, the correct answer is D.