Answer:
Gorbachev's decision to loosen the Soviet yoke on the countries of Eastern Europe created an independent, democratic momentum that led to the collapse of the Berlin Wall in November 1989, and then the overthrow of Communist rule throughout Eastern Europe.
Explanation:
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The Aztecs focused on agricultural innovations, while the Incas focused on agricultural innovations.
The Vaco de gama voyage they were trying to achieve land in Africa.
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It could be A or C, i'm not too sure