Question

due to paranoia, hitler invaded his own ally, _______________. russia turkey japan austria

Explanation:

Hitler and the Soviet Union (referred to here as Russia) had a non-aggression pact (Molotov-Ribbentrop Pact) making them de facto allies initially in WWII. Driven by paranoia and expansionist goals, Hitler launched Operation Barbarossa, invading the Soviet Union in 1941. The other options were not his allies at the time of the invasion; Turkey was neutral early on, Japan was a separate Axis ally not invaded by Hitler, and Austria was annexed earlier before the pact with the Soviet Union.

Answer:

Russia