Final answer:
The Marine Corps Good Conduct Medal was established by Executive Order 8809, signed by President Franklin D. Roosevelt on June 27, 1941, to honor Marines for exemplary conduct.
Step-by-step explanation:
The Marine Corps Good Conduct Medal (MCGCM) was established to recognize good behavior and faithful service in the Marine Corps. The authority responsible for the creation of the MCGCM is Executive Order 8809, signed by President Franklin D. Roosevelt on June 27, 1941. This medal is a significant decoration for Marines who demonstrate exemplary conduct during a specified period of active enlisted service. Executive Order 8809 established the Marine Corps Good Conduct Medal (MCGCM) to recognize good behavior and faithful service in the Marine Corps
Answer: A) Executive Order 8809