You are called to a local park for an ill person. It is a hot day and the humidity is high. When you arrive, a bystander directs you to the patient, a young male who is semiconscious. His skin is flushed, hot, and moist. Your FIRST action in the management of this patient should be to:
A) Administer high-flow oxygen
B) Begin CPR
C) Move the patient to a cool environment
D) Remove the patient's clothing