Final answer:
Executive Order 9981, issued by President Truman in 1948, ended segregation in the military and promoted equal opportunity for all members regardless of race, ethnicity, or religion.
Step-by-step explanation:
Executive Order 9981, issued by President Truman in July 1948, declared an end to segregation in the military and mandated that all members of the military be given equal opportunity regardless of their race, ethnicity, religion, or national origin. The order paved the way for the integration of the armed forces and was a significant step towards promoting civil rights in the United States.