Which one of the following is not an ASEAN member?

The Association of Southeast Asian Nations (ASEAN) was established in 1967 by five founding members: Indonesia, Malaysia, the Philippines, Singapore, and Thailand [3]. Over the subsequent decades, the organization expanded to include Brunei Darussalam (1984), Vietnam (1995), Laos (1997), Myanmar (1997), and Cambodia (1999), bringing the total to ten member states [4]. While Timor-Leste has recently been granted observer status and is on a path toward permanent membership, Taiwan is not a member of ASEAN [4]. Taiwan's exclusion is consistent with the organization's focus on sovereign Southeast Asian states and the geopolitical complexities surrounding the 'One China' policy. Cambodia, Laos, and Myanmar are all officially recognized members that joined during the late 1990s enlargement phase [3]. Therefore, Taiwan is the only option listed that is not an ASEAN member.

Sources

1. [1] Contemporary World Politics, Textbook in political science for Class XII (NCERT 2025 ed.) > Chapter 2: Contemporary Centres of Power > 20 Contemporary World Politics > p. 20
2. [3] Indian Economy, Nitin Singhania .(ed 2nd 2021-22) > Chapter 18: International Economic Institutions > ASEAN > p. 550
3. [2] https://asean.usmission.gov/policy-history/
4. [4] https://www.cfr.org/backgrounder/what-asean