Which of the following is NOT a reason for formation of regional blocs?

none of the above.

The correct answer is option 4: none of the above.

All the given statements are valid reasons for the formation of Regional Trade Blocs.

Option 1: to encourage trade between countries with geographical proximity. This is a correct reason because nearby countries can trade more efficiently.

Option 2: similarity and complementarities in trading items. This is also a correct reason as countries benefit when their trade goods complement each other.

Option 3: to curb restrictions on trade of the developing world. This is another correct reason since regional blocs aim to reduce trade barriers.

NCERT :Regional Trade Blocs have come up in order to encourage trade between countries with geographical proximity, similarity and complementarities in trading items and to curb restrictions on trade of the developing world. Today, 120 regional trade blocs generate 52 per cent of the world trade. These trading blocs developed as a response to the failure of the global organisations to speed up intra-regional trade.