The countries in European Union are linked as they have a single common currency and they allow people to move easily between the countries.
Option C and D
<h3><u>Explanation:
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Only one market system was established by The European Union. It has been established in all its territories and has about 513 millions. Since there do not exists any differences in the currency it helped trading a lot. EU is the world's largest exporter.
Euro is used as a common currency. This is under Eurozone, which is the Monetary union. The number of states joined this union is 19. This union has 342 million EU citizens as its member. After the US dollar, Euro is the currency that is used in trading among different countries and it hold the second position in the reserve currency list. The countries under European Union allow people to move from one country to another. They can study in one country and work in some other country of European Union.
An appositive is a phrase or a word that renames a noun right beside it. Among the choices listed, the best answer is option C. <span>One cause of erosion, wind, can create alterations in the surface layers of rock. Erosion here renames wind.</span>
