A medical officer with the fleet surgical team, USS San Diego, examines a role-playing injured Marine on the quarter deck of the USS San Diego as part of a mass casualty drill conducted during Certification Exercise (CERTEX) off the coast of Southern California, June 15, 2014. CERTEX is the final evaluation of the 11th Marine Expeditionary Unit and Makin Island Amphibious Ready Group prior to deployment. The evaluation requires the Marines and sailors to plan and conduct integrated missions simulated to reflect real-world operations. (U.S. Marine Corps photo by Gunnery Sgt. Rome M. Lazarus/Released)