Final answer:
The exact year the "V" device was authorized for wear on specific military medals is not provided in the provided reference information, requiring further research on military awards and decorations.
Step-by-step explanation:
The year the "V" device was authorized for wear on military decorations such as the Legion of Merit, Distinguished Flying Cross, Bronze Star Medal, Air Medal (Individual Award), Navy and Marine Corps Commendation Medal, and Navy and Marine Corps Achievement Medal is not specifically mentioned in the information provided. In the United States Armed Forces, the "V" device is used to denote valour in combat and can be attached to certain medals to indicate that the award was earned for acts of combat heroism or service. As the history of various military decorations can involve multiple revisions and authorizations, pinpointing the exact year of authorization for the "V" device across all these medals would typically require a direct reference to military regulations or historical documents concerning military awards and decorations.