A. a common market, a free trade area, an economic union, a customs union, and a political union.
B. a free trade area, a customs union, a common market, an economic union, and a political union.
C. a customs union, a free trade area, a common market, a political union, and an economic union.
D. a common market, an economic union, a customs union, a free trade area, and a political union.