The correct answer is "D".
The United States gained control of the Island of Guam and the Philippine islands after the end of World War 2. This happened as a result of the defeat of the Japanese Empire to the Americans during the Campaign of the Pacific.
The Japanese had initially expanded their control over these territories but subsequent military losses, including the one, occurred during at the Battle of Midway on June 7th, 1942, led to them forcing to retreat, ceding the land to the United States.
Guam would remain as an organized territory of the United States, while the Philippine Islands would go back to the government of the Philipines after a period of American colonization.