A security guard responds to a person who has collapsed and is unconscious, but appears to be breathing normally. After calling EMS, what is the most appropriate next step for the guard?

1. Attempt to wake the person by shaking them vigorously and shouting.
2. Administer an over-the-counter pain reliever if available.
3. Place the person in the recovery position and continuously monitor their breathing.
4. Begin chest compressions immediately, as unconsciousness indicates cardiac arrest.