The United States entered the fighting of World War II in 1941, though hostilities had been taking place in Europe since 1939. Which of the following best describes the grand strategy employed by the United States, Great Britain, and the other Allied Forces in World War II?

A. The Allies decided to evenly split their manpower between both the European Theater and the Pacific Theater.
B. The United States agreed to help in the European Theater only after the U. S.S. R pledged to open an eastern front.
C. The United States supplied manpower only to the Pacific Theater, leaving the other Allies to defeat Germany.
D. The Allies agreed to use the bulk of their resources to defeat Nazi Germany first before focusing on Japan.