A. Italy
B. Spain
C. Brazil
D. Mongolia
Details of The longest land border of France:
Due to the French province of French Guiana on the continent of South America, France has the longest land border with Brazil. The border is the longest that France shares with another nation, measuring roughly 730 kilometers (450 miles). This may come as a surprise because when most people think of France, they mainly think of its European side. But legally speaking, French Guiana is the same country as mainland France in Europe. That land is fully part of France, so the longest border of France is not in Europe but rather that of that territory with Brazil.
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