Answer :
Reduction in Civil Liberties was the policy that the United States implemented in postwar Japan.
In post-war Japan, the United States implemented a policy of "rebuilding the nation." Option A is correct.
In the wake of World War II , Japan was devastated. All the large cities ( except from Kyoto), the industries and the transportation networks were severely damaged. Furthermore, severe shortage of food continued for several years.
The occupation of Japan by the Allied Powers started in August 1945 and ended in April 1952. General MacArthur was its first Supreme Commander. The whole operation was carried out by the United States.