Answer:
The correct answer is 2. The defeat of Japan led to the division, with a Soviet-backed communist government in the north and a U.S.-backed democratic government in the south.
Step-by-step explanation:
At the suggestion of US General Douglas MacArthur, in October 1943 the heads of state of the United States and the USSR met in Moscow and agreed that the USSR would declare war on Japan once the war in Germany had ended. This decision was supported by the belief that the Japanese Empire was more vulnerable in the north, in Manchuria and Korea, than in the south, in the Philippines, where it was winning the battles.
On August 8, 1945, two days after the atomic bombing of Japan in Hiroshima by the US, the USSR declared war on Japan and the next day attacked the Korean peninsula in the north. This decision alarmed the United States, that after the atomic bombings on Japan, thus ensuring the early Japanese surrender, were no longer interested in the entry of the Soviet Union into the war. One day after the second atomic bombing of Japan in Nagasaki on August 10, 1945, the United States sends troops to Busan, south of the Korean peninsula. Korea, on the other hand, counted on a guerrilla of communist ideology that faced Japan and supported the measures of the USSR. The American troops were also well received at their landing in Busan, to the south.
On August 10, when preparing the general surrender of Japan, the Operations Division of the US Department of War chose the 38th parallel as the boundary of the country's defense. On August 15 the surrender was published. Joseph Stalin, in a climate of growing tension between the United States and the Soviet Union, ordered his troops to stop north of the 38th parallel, while US troops were stationed south of it at the same time. Stalin admitted the surrender of Japan and said nothing about the division of Korea. The Americans took this act as an acceptance of the division.