Final answer:
Imperialism is the factor among the 4 MAIN factors that led to WWI which called for the expansion of a nation.
Step-by-step explanation:
Imperialism is the factor among the 4 MAIN factors that led to WWI which called for the expansion of a nation. Imperialism refers to a policy or ideology of extending a nation's power and influence through colonization, conquest, or economic dominance over other territories or nations.
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