Question: What was the last major German offensive on the Western Front during the First World War, Second Battle of the Marne or Battle of Pusan Perimeter?
Sentence (from "Hindenburg Line"): Construction of the Hindenburg Line in France was begun by the Germans in September 1916, to make a retirement from the Somme front possible, to counter an anticipated increase in the power of Anglo-French attacks in 1917.
Relevant evidence: No