Correct answer:
Japan
Japan had taken annexed Korea already in 1910 as part of its imperial aggression and expansion in Asia. Japan continued to maintain control of Korea until the final year of World War II, in 1945. Soviet forces battled Japan in Asia in the later part of 1945. After the USA dropped atomic bombs on Japan in August, 1945, Soviet forces moved into Korea from the north. American forces took over in the south. From then on, the country was divided at the 38th parallel between a communist northern half and democratic southern half.