Final answer:
The patient who should be seen first is the 16-year-old football player who was injured and has slurred speech and confusion. The combination of an injury and neurological symptoms indicates a potentially serious condition that requires immediate medical attention.
Step-by-step explanation:
The patient who should be seen first is patient D, the 16-year-old football player who was injured and has slurred speech and confusion. The combination of an injury and neurological symptoms indicates a potentially serious condition that requires immediate medical attention. This could be a sign of a concussion or other head injury, and prompt evaluation is necessary to assess the severity of the injury and provide appropriate care.