B) One unit of packed red blood cells (PRBCs)
D) Normal saline solution
Explanation: A) Foreign material is, essentially, anything from outside the body. Autologous stems cells, thromboemboli, and renal calculi all originate within one's own body, and are therefore not considered foreign materials.
B) Packed red blood cells from another person originate outside one's own body, and are therefore considered a foreign material.
C) Foreign material is, essentially, anything from outside the body. Autologous stems cells, thromboemboli, and renal calculi all originate within one's own body, and are therefore not considered foreign materials.
D) Normal saline solution does not originate within one's own body, and is therefore considered foreign material.
E) Foreign material is, essentially, anything from outside the body. Autologous stems cells, thromboemboli, and renal calculi all originate within one's own body, and are therefore not considered foreign materials.