Final answer:
When assessing a critical patient entrapped in a small sedan with significant intrusion, the crew member should concentrate on assessing the head, chest, and torso.
Step-by-step explanation:
When assessing a critical patient entrapped in a small sedan with significant intrusion into the occupant area, the crew member should concentrate on assessing the head, chest, and torso of the patient. These areas are crucial because they contain vital organs and major blood vessels. By assessing these areas, the crew member can determine the extent of the patient's injuries and provide appropriate treatment.