What Developments Played in Germany's Favor in the Years Leading

What developments played in Germany's favor in the years leading up to ​World War II?

A) France adopted a mainly defensive posture with the building of the Maginot Line.
B) Britain and, subsequently, France adopted a policy of appeasement in the hopes of mellowing Hitler.
C) the United States seemed unconcerned with events in Europe.
D) Germany had secret agreements to train pilots and tank corpsmen in the Soviet Union.
E) all of the above