Recruiters serve as the entry into the Corps through a variety of means. While the majority of accessions are enlisted, those who qualify can attempt to earn a commission and become an officer. All potential recruits are screened by recruiters for physical standards and fitness, adequate education (a high school diploma or equivalent, such as a GED for enlisted, and a bachelor's degree for officers), lack of significant civil convictions, lack of significant drug use, and other qualifiers. The Armed Services Vocational Aptitude Battery is administered to determine qualifications for a job field (known as a Military Occupational Specialty).[1] Enlisted Marines who qualify and successfully process through a Military Entrance Processing Station can ship to recruit training. Recruits from the 1st, 4th, and 6th Marine Corps Districts will attend Marine Corps Recruit Depot Parris Island, while males from the 8th, 9th, and 12th will attend Marine Corps Recruit Depot San Diego. All enlisted females attend recruit training at Parris Island, regardless of district.[2] Officers can be sourced from several veins: Officer Selection by Recruiting Stations, Naval Reserve Officer Training Corps, and enlisted commissioning. The vast majority will train at Officer Candidates School, but some will attend the Naval Academy instead.