(A) A system of strategic fortifications
(B) Outwaiting their opponents
(C) The ability to make a long, steady advance
(D) ** Surprise attack followed by overwhelming force
EXPLANATIONS BELOW
Concept note-1: -Radio communications were the key to effective Blitzkrieg operations, enabling commanders to coordinate the advance and keep the enemy off balance. These techniques were used to great effect in 1939, when the Polish Army was destroyed in a series of encirclement battles.
Concept note-2: -The Germans used blitzkrieg tactics to startling effect in Poland (1939), France (1940), Russia (1941), and the Ardennes (1944), although technically speaking, true blitzkrieg ala Guderian was used only in the first two campaigns (Guderian would later be sacked for disagreeing with Hitler’s decisions in Russia).
Concept note-3: -Seventy-five years ago, on June 22, 1941, Nazi Germany attacked the Soviet Union, betting on a brief war with the firmest of goals, a type of war that came to be known as blitzkrieg. By June 1941 the German Wehrmacht had evolved into one of the most powerful and effective military machines in history.