To measure gender differences in terms of wealth, health, and education, the appropriate choice would be the Gender Development Index (GDI). The GDI specifically focuses on these dimensions and compares the achievements of men and women, making it suitable for analyzing gender disparities in those areas.
The other options, like GDP and the GINI coefficient, measure overall economic performance and income inequality, respectively, but do not specifically target gender differences. The Consumer Price Index (CPI) measures inflation and cost of living changes and is not directly related to gender differences in wealth, health, and education either.