Scenario: Moonland Union Twenty-Six Nations,A Through Z Countries of Moonland Region,have Decided to Region,have

Scenario: Moonland Union
Twenty-six nations,A through Z countries of Moonland region,have decided to cooperate with one another to eliminate trade barriers among them and create Moonland Union.They are not sure,however,to what extent they want to cooperate.
-If these 26 nations continue to eliminate all barriers to trade among themselves and erect a common trade policy against non-members,they would create a(n) ________.

A) free trade area
B) economic union
C) customs union
D) common market