Answer:
During World War II, the federal government became heavily involved in US industry in order to support the war effort. In order to do this, they changed the focus of industry to make it war-oriented. This involved directing industries to produce goods and materials that were needed for the war, such as weapons, vehicles, and clothing for soldiers. The government also provided funding and resources to support this effort, and implemented regulations and policies to ensure that industries were able to meet the demands of the war. The goal of this involvement was to increase the production of war-related goods and materials, and to support the war effort in any way possible. Therefore, the correct answer is option D: They changed the focus of industry to make it war-oriented.