a 68-year-old man was choking on a piece of steak at a family restaurant. despite attempts to dislodge the food via abdominal thrusts (or the heimlich maneuver), his upper airway remained blocked. an emergency medical technician (emt), eating at the scene, performed an emergency procedure involving making an incision in a component of the conus elasticus to enable the man to breathe. which subcutaneous structure was most likely cut during this procedure?