What does USMC stand for?

The correct answer is B, which stands for the United States Marine Corps. This is an essential branch of the U.S. military, primarily responsible for amphibious operations and providing expeditionary forces. The Marine Corps emphasizes combined arms and rapid-response capabilities, often playing a crucial role in national defense and crisis response missions.

Understanding the distinction among the options clarifies why B is correct. The other choices either reference broader military organizations or inaccurately represent the specific name of the Marine Corps. For example, "United States Military Command" and "United States Military Corps" do not accurately capture the unique identity and functions of the Marine Corps as a separate and specialized branch of service. "United States Marine Command," while it includes the term "Marine," does not represent the official title of the branch. Therefore, the designation "United States Marine Corps" is the accurate and recognized name of the institution.