The School Nurse Has Been Called to the Football Field

The school nurse has been called to the football field where player is immobile on the field after landing awkwardly on his head during a play. While awaiting an ambulance, what action should the nurse perform?

A) Ensure that the player is not moved.
B) Obtain the players vital signs, if possible.
C) Perform a rapid assessment of the players range of motion.
D) Assess the players reflexes.