Final answer:
Women played a crucial role in the U.S. Sanitary Commission, serving as nurses who improved camp conditions, assisted the wounded, and helped reduce disease among soldiers.
Step-by-step explanation:
The involvement of women in the U.S. Sanitary Commission, a government-sponsored nursing corps that provided aid to wounded soldiers during the war, is best described by: Option 3: Women played a vital role in the nursing corps. Women in the North volunteered for the United States Sanitary Commission, where they inspected military camps to improve cleanliness and aimed to reduce the number of soldiers dying from diseases, which was the predominant cause of death. They raised funds for medical supplies and assisted with nursing the injured. In addition to these roles, women also served as cooks, laundresses, and even spies during the war. Notably, Dorothea Dix called upon women to serve as nurses for the Union army, emphasizing the need for them to be respectable and not engaging in romantic involvements with soldiers.