The correct answer to this open question is the following.
Although there are no options attached we can say the following.
The two advantages that Japan had after World War II that benefitted its recovery were the following.
First, the fact that the reconstruction of Japan was led by the United States and the Allied Forces from 1945 to 1952 under the leadership of US General Douglass McArthur. He established a series of social, economic, and political reforms that benefited Japan's reconstruction.
Secondly, McArthur was the leader of the Supreme Command of Allied Powers SCAP.
Secondly, that all was possible thanks to the committed discipline and determination of the Japanese people. Japanese people have a one-of-a-kind discipline, focus, perseverance, and hard work ethic, second to none in the world. That disciple and hard work make them overcome the difficult situation in a relatively few years.