39. The Human Development Index (HDI )

a. goes beyond a purely income-based measure of development.

b. significantly alters the overall assessment of which countries are more or less developed, compared to incomebased assessments.

c. incorporates measures of the ends (i.e. goals) of human well-being but no measures of the means (i.e. instruments) of human well-being.

d. all of the above.