U.S. Marine Candidates participate in an endurance

U.S. Marine Candidates participate in an endurance course training exercise at the Officer Candidate School, Marine Corps Base Quantico, Va., July 11, 2017. Candidates must go through three months of intensive training to evaluate and screen individuals for the leadership, moral, mental, and physical qualities required for commissioning as a U.S. Marine Corps officer. (U.S. Marine Corps photo by Lance Cpl. Yasmin D. Perez)