Which was associated with the western front?

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The Western Front began with the German invasion of Belgium in 1914. The invasion, the opening step of an invasion of France, violated Belgium’s neutrality, prompting the entrance of Great Britain and its allies into the war. For four years and despite many bold attempts to gain advantage by both sides, neither the Allied or Central Powers managed to make significant progress toward victory.Some of the most enduring images of the war originated in the Western Front during this time, including trench warfare, chemical weapons, aerial combat, and tank battles. The Western Front was eventually won in 1918 by Allied Forces during the Hundred Days Offensive. Beginning with the Battle of Amiens, the Allies pushed their enemies back over their defensive Hindenburg Line, persuading German officers of the inevitability of surrender.

The answer is a c b d a c b d