Answer:
D. Imperialism.
Step-by-step explanation:
By definition, Imperialism is, quote "a policy of extending a country's power & influence through diplomacy or force".
In this case, Germany uses force, as exemplified by the following quotes:
"Germany began taking over other countries." (General)
"... Germany invaded Poland in 1939..." (Specific)
Therefore, D. Imperialism is your answer.
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