‘They are fantastically diverse. They speak hundreds of languages and dialects. They comprise scores of ethnic groups. They include highly industrialised economies and up-and-coming economies. They span half the surface of the earth and are home to two-fifths of the world’s population.” The group of countries referred to here belongs to

The quotation refers to the Asia-Pacific Economic Cooperation (APEC). APEC is a diverse regional economic forum covering the Asia‑Pacific, bringing together highly industrialised and emerging economies across a vast geographic area — a description echoed in the cited question text. Official sources note APEC’s 21 member economies span the Asia‑Pacific and aim to foster trade and investment cooperation [1], while reporting shows APEC members account for roughly 40% of the world’s population and over half of global GDP, matching the “two‑fifths” and major‑economy mix in the passage [1]. These combined facts identify APEC as the correct grouping.

Sources

1. [2] https://www.apec.org/about-us/about-apec
2. [1] https://www.reuters.com/world/china/what-is-apec-asia-pacific-leaders-gather-south-korea-2025-10-28/