4 May is observed as –

International Cooperative Day
United Nations Day for South-South Cooperation
European Day of Languages
International Firefighter's Day

The correct answer is: A. International Cooperative Day

International Cooperative Day is celebrated on the first Saturday of July every year. It is a day to celebrate the achievements of cooperatives and to promote the cooperative movement. The day was first celebrated in 1923, and it was officially recognized by the United Nations in 1995.

Cooperatives are businesses that are owned and operated by their members. They are based on the principles of cooperation, democracy, and self-help. Cooperatives are important because they provide a way for people to work together to meet their common needs. They can also help to promote economic development and social justice.

There are many different types of cooperatives, including credit unions, housing cooperatives, and worker cooperatives. Cooperatives can be found in all parts of the world, and they play an important role in the global economy.

Here are some brief descriptions of the other options:

  • B. United Nations Day for South-South Cooperation is celebrated on 20 December every year. It is a day to promote South-South cooperation, which is the cooperation between developing countries. South-South cooperation can take many forms, such as trade, investment, technology transfer, and capacity building.
  • C. European Day of Languages is celebrated on 26 September every year. It is a day to celebrate the diversity of languages in Europe and to promote multilingualism. The day was first celebrated in 2001, and it was officially recognized by the European Parliament in 2002.
  • D. International Firefighter’s Day is celebrated on 4 May every year. It is a day to recognize the work of firefighters and to thank them for their service. The day was first celebrated in 1999, and it was officially recognized by the United Nations in 2001.