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

Option A is correct. Argentina, Mexico, South Africa and Turkey are all G20 members. The G20 has 19 countries plus the European Union. It began in 1999 as a finance ministers' forum after the Asian financial crisis and was raised to leaders' level in 2008 during the global financial crisis.

Why the others fail:

• B: Malaysia and New Zealand are not members. Australia and Canada are, which is why this option looks tempting.
• C: Iran and Vietnam are not members. Brazil and Saudi Arabia are.
• D: Singapore is not a member, though Indonesia, Japan and South Korea are.

Core concept: membership of multilateral forums such as the G20, G7, BRICS and APEC. For Mains GS-2 (international institutions), the G20 matters for global economic governance. India held the presidency in 2023, and the African Union became a permanent member in September 2023, so update that fact if your notes are older.

Trap: candidates mix the G20 with APEC or ASEAN, which include Malaysia, Vietnam, Singapore and New Zealand. Check each country against the G20 list rather than relying on regional familiarity.