10 In the World Bank's classification system, countries are ranked by their levels of Gross National Income (GNI) per capita. A significant number of countries are grouped as "other high-income countries" because but of . a. They are not part of the OECD countries. O b. They have poor health system, most of their population are uneducated and their social development is viewed as low. c. They are considered as developing countries because they are not a part of Western countries. d. Despite the fact that their GNI is low, their excellent education and healthcare systems promoted them to the level of high-income countries. Clear my choice