In Which Area Was the Nazi Rule of Europe Most

In which area was the Nazi rule of Europe most ruthless?

A) Eastern Europe, because the Slavs were considered racially inferior
B) France, due to the long rivalry between France and Germany
C) Norway, Denmark, and the Netherlands, due to their close proximity to Germany.
D) Italy, because the Italians were generally considered to be disloyal.
E) Greece and Yugoslavia, because of the strategic nature of the Balkans region.