Answer:
Common market.
Explanation:
In this scenario, Countries A, B, and C are at a particular level of economic integration. All these countries enjoy reduced or eliminated internal tariffs on trade between them and have added a common external tariff on products imported from countries outside the union. If these countries remove all restrictions on the free flow of capital and labor among themselves, they represent a common market.
A tariff can be defined as a form of taxation employed by a country and applies to imported goods or services from another country.
A common market refers to a formal organization of countries who have collectively agree to trade freely with one another with reduced or eliminated internal tariffs but imposes a common external tariff on trade with other countries. It was founded in 1958 and was made up of countries like Luxembourg, France, Belgium, Netherlands, West Germany and Italy.
The main purpose and advantage of the common market is that, it avails member countries the opportunity to move goods, people, services and capital freely.