Which of the Following Was NOT a Major Contributing Factor

Which of the following was NOT a major contributing factor to the eventual Soviet victory against Germany?

A) The successes of Blitzkrieg which created extended supply lines
B) Relentless propaganda campaigns designed to convince Germany's allies of the Nazis' unreliability and the hopelessness of their cause
C) The recovery of Soviet industry after the initial German attack
D) The hard blows of the Russian winter against the lives, supplies, and morale of Axis forces unprepared for the bitter weather
E) The willingness of Russian military leaders to sacrifice large numbers of their own soldiers to ultimately defeat the Germans