The correct answer is letter A.
Meuse-Argonne Offensive was part of the final Allied offensive during World War I that took place along the Western Front. The whole offensive was planned by the French commander Ferdinand Foch who sought to violate the so-called Hindenburg Line and thereby give an ultimatum and force the capitulation of the Germans. During September and October the allies crossed the line in various directions (north, center and south) - operations that included the Battle of the Argonne Forest - and carried out what is often remembered as the Great Offensive (also called the "Hundred Days Campaign").