First of all, five socialist countries are now recognized: China, North Korea, Cuba, Viet Nam and Laos. None of these five countries is a member of the Organization of Petroleum Exporting Countries, so B can be excluded.

Secondly, the organization has 1 1 members, and no member's per capita income is low enough to meet the standards of poor countries, so A is excluded.

Finally, among the 1 1 countries, there are rich and developed countries such as Saudi Arabia, Kuwait and Qatar with per capita income of 1 10,000 dollars, as well as developing countries such as Indonesia, Venezuela and Nigeria.

So I chose CD.