They’re the NCAA teams for the US Military Academy (West Point), Naval Academy, and Air Force Academy. The Coast Guard and Merchant Marine also have service academies but they play in D3. The Academies are degree-granting undergrad colleges in addition to being military training institutes, and their players are college students as well as active duty members of the military. When they graduate they’re commissioned as officers in their respective services. The Naval Academy also commissions officers into the Marine Corps (about 25% of each graduating class).
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