You are transporting an elderly female who fell in a nursing home and displays outward rotation of her left leg. She has a lengthy medical history, including dementia. Currently, she is very quiet and receiving oxygen through a nasal cannula at 6 liters per minute. She also is secured to a long spine board. During your reassessment, you note her to be alert but confused, with slightly accelerated respirations and a strong radial pulse. You also note that her SpO2 has dropped from 97% on scene to 91%. You should:

A) Perform a head-tilt, chin-lift maneuver
B) Request ALS assistance
C) Apply supplemental oxygen
D) Start positive pressure ventilation

C) Apply supplemental oxygen