(A) Prussia
(B) ** The Rhineland
(C) The Saar
(D) The Ruhr
EXPLANATIONS BELOW
Concept note-1: -According to the Treaty of Versailles, the Rhineland, a strip of land inside Germany bordering on France, Belgium and the Netherlands, was to be de-militarised.
Concept note-2: -To prevent any new attack upon France or Belgium, by the treaty of Versailles, Germany was forbidden to keep soldiers or maintain fortifications in the Rhine valley. The Rhineland was to be occupied by the Allies. The area on the east bank of the Rhine was to be demilitarised.
Concept note-3: -The Versailles Treaty forced Germany to give up territory to Belgium, Czechoslovakia and Poland, return Alsace and Lorraine to France and cede all of its overseas colonies in China, Pacific and Africa to the Allied nations.
Concept note-4: -Finally, the Rhineland was demilitarized; that is, no German military forces or fortifications were permitted there. In the east, Poland received parts of West Prussia and Silesia from Germany.
Concept note-5: -The remilitarization of the Rhineland (German: Rheinlandbesetzung) began on 7 March 1936, when German military forces entered the Rhineland, which directly contravened the Treaty of Versailles and the Locarno Treaties. Neither France nor Britain was prepared for a military response, so they did not act.