What is a ruling body that runs the affairs of a country?

A ruling body that runs the affairs of a country is typically referred to as the government. It comprises various branches, such as the executive, legislative, and judicial, which work together to create and enforce laws, implement policies, and manage public services. The structure and function of a government can vary widely depending on the country's political system, whether it be democratic, authoritarian, monarchy, or otherwise. Ultimately, the government is responsible for maintaining order, providing for the welfare of its citizens, and representing the nation's interests.