When arriving first at the scene of a traffic accident with an unconscious casualty, what is the correct initial assessment sequence?

1. Immediately feed the victim hot liquids and shake them vigorously.
2. Check responsiveness (consciousness), open airway, verify breathing, and check for circulation/severe bleeding (ABC protocol).
3. Pull the victim upright into a sitting posture.
4. Search the victim's pockets for personal identification cards before checking breathing.