Final answer:
The Prague Spring occurred in Czechoslovakia in 1968 and was a period of political liberalization and reform.
Step-by-step explanation:
The correct answer is OD) Czechoslovakia. The Prague Spring was a period of political liberalization in Czechoslovakia that took place in 1968. It was led by Alexander Dubcek and aimed to bring about democratic reforms and greater autonomy from the Soviet Union. This movement was eventually suppressed by the Soviet Union and other Warsaw Pact countries.
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