Final answer:
Executive Order 9981 delegated the authority to prescribe clothing or cash allowances for enlisted personnel to the Secretary of Defense, thereby ending segregation in the military.
Step-by-step explanation:
The executive order that delegated the authority to prescribe the quantity and kind of clothing or cash allowances in lieu of clothing, for enlisted personnel, to the Secretary of Defense is Executive Order 9981. This order was issued by President Truman in July 1948 and was in response to demands by black leaders. It declared an end to segregation in the military and required equal opportunity for all members regardless of their race, ethnicity, religion, or national origins.