Explanation:

All codes are correct.

Association of Southeast Asian Nations (ASEAN)

• ASEAN is an international organization established by the governments of Indonesia, Malaysia, the Philippines, Singapore, and Thailand in 1967.

• It aims to accelerate economic growth and promote peace and security in Southeast Asia.

• Brunei joined in 1984, followed by Vietnam in 1995, Laos and Myanmar in 1997, and Cambodia in 1999.

• East Timor has been granted observer status and is expected to become a full member in 2025.

• ASEAN Regional Forum – It aims to foster constructive dialogue and consultation on political and security issues of common interest and concern.

• It makes significant contributions to efforts towards confidence-building and preventive diplomacy in the Asia-Pacific region.

The current participants in the ARF are:

• Australia, Bangladesh, Brunei Darussalam, Cambodia, Canada, China, Democratic People’s Republic of Korea,

• European Union, India, Indonesia, Japan, Lao PDR, Malaysia, Mongolia, Myanmar, New Zealand, Pakistan, Papua New and

• Guinea, Philippines, Republic of Korea, Russia, Singapore, Sri Lanka, Thailand, Timor-Leste, United States, and Viet Nam.

Expanded ASEAN Maritime Forum (EAMF) – It was established in 2012 as a Track 1.5 Forum with a view to engage the several countries in a dialogue on important maritime issues of common interest.

• The countries include Australia, China, India, Japan, New Zealand, Republic of Korea, Russia, and the United States of America.

ASEAN Defence Ministers' Meeting Plus – Is a platform for ASEAN and its 8 Dialogue Partners Australia, China, India, Japan, New Zealand, Republic of Korea, Russia and the United States (collectively referred to as the “Plus Countries”).

• It aims to strengthen security and defence cooperation for peace, stability and development in the region.

East Asia Summit – It comprises 18 participating countries, including 10 ASEAN Member States.

• The member states includes Brunei Darussalam, Cambodia, Indonesia, Lao PDR, Malaysia, Myanmar, Philippines, Singapore, Thailand, Viet Nam, and Australia, China, India, Japan, New Zealand, the Republic of Korea, the Russian Federation, and the United States of America.

Hence option 4th is correct.