European countries officially created a when they established the eec.

C.  common market

Explanation:

European economic community was a  regional organization that aimed to bring a integration in the member states with a treaty of Rome in 1957. And its need was to establish a single market system. A common custom union to the Belgium, France, Italy and western Germany, Luxembourger and Netherlands. In the year 1994, the market was established and formalized by the European Economic Area agreements, forming a free trade association among 15 countries.

Answer carbon dioxide ice;