What is the full form of ASEAN?

The correct answer is Option (3) → Association of South East Asian Nations

ASEAN stands for Association of South East Asian Nations.

ASEAN was established in 1967 by five countries of this region — Indonesia, Malaysia, the Philippines, Singapore and Thailand — by signing the Bangkok Declaration. The objectives of ASEAN were primarily to accelerate economic growth and through that ‘social progress and cultural development’. A secondary objective was to promote regional peace and stability based on the rule of law and the principles of the United Nations Charter.