In which one of the following groups are all the four countries members of G20?

1. The question asks to identify the group where all four countries are members of the G20. 2. The G20 comprises 19 countries plus the European Union. The 19 countries are: Argentina, Australia, Brazil, Canada, China, France, Germany, India, Indonesia, Italy, Japan, Republic of Korea (South Korea), Mexico, Russia, Saudi Arabia, South Africa, Turkey, the United Kingdom, and the United States. 3. Analyzing the options: (A) Argentina, Mexico, South Africa, and Turkey are all G20 members. (Correct Group) (B) Malaysia and New Zealand are not G20 members. (C) Iran and Vietnam are not G20 members. (D) Singapore is not a G20 member (though often invited as a guest). 4. Therefore, the group containing only G20 member countries is (A).