In a common market, member countries agree basically to

In a common market, member countries agree to establish common barriers against countries outside the market. A common market is an agreement between two or more countries to establish a free trade area, where goods, services, and capital can move freely across borders. In a common market, member countries eliminate tariffs and other trade barriers on goods and services traded between them. However, member countries also establish common barriers against countries outside the market to protect their economies from unfair competition. For example, they may impose tariffs, quotas, or other trade barriers on imports from non-member countries. In addition, member countries in a common market may negotiate with countries outside the market for favourable terms of trade. By negotiating as a bloc, they can have more leverage in trade negotiations and secure better deals for their member countries. Therefore, the correct option is negotiate with countries outside the market for favourable terms of trade.