The best answer is C) Japan was in a key strategic location in the Pacific Ocean.
The American occupation of Japan lasted until the signing of the San Francisco Peace Agreement, which took place in 1951. From 1952 Japan became an "independent" country again, and American occupation troops left the country as stipulated the deal. During the American occupation, Japan was forbidden to possess armed forces (later the United States allowed Japan to possess up to 350,000 men to secure the nation's internal security).
Japanese infrastructure and economy were completely destroyed in 1945. Inflation was out of control, and the population often found only staples on the black market. In addition, the Soviet shadow represented to the United States a great risk to its geopolitical interests in Asia.
From an economic partnership between the United States and Japan, the restructuring of the Japanese nation was possible. Moreover, during the American occupation, the United States did not allow Soviet troops to occupy part of the Japanese territory, which ended up distancing any Soviet influence in Japan.