An Army specialist ranks immediately below a ______________.

The rank of Army specialist falls directly below that of corporal in the U.S. Army rank structure. Specialists are considered to be in the junior enlisted tier, but they hold a higher position and responsibility than privates who are at the base level of the enlisted ranks. A corporal, although also an enlisted rank, carries additional leadership responsibilities and is a non-commissioned officer (NCO). The specialist rank does not confer the same level of responsibility, making it crucial to identify that corporal is the rank immediately superior to specialist.

In this context, the other ranks listed, such as private, sergeant, and lieutenant, do not accurately reflect the immediate rank above specialist. Private is lower than specialist, while sergeant and lieutenant are higher ranks, indicating increased levels of authority and responsibility compared to a specialist and corporal. Thus, the correct answer is that an Army specialist ranks immediately below a corporal.