Final answer:
The patient who requires immediate attention and should be assigned a red tag is the 22-year-old male with blunt abdominal trauma, evidenced by tachycardia, pallor, and diaphoresis indicating likely internal bleeding and shock.
Step-by-step explanation:
Among the patients listed, the one who should be assigned an immediate (red tag) category in a triage situation is the 22-year-old male with blunt abdominal trauma, tachycardia, pallor, and diaphoresis. This individual is displaying signs of internal bleeding and shock, which are life-threatening conditions needing immediate medical attention. Conditions such as numbness and tingling in the extremities, an open fracture, and even an open head injury with agonal breathing and a slow pulse rate, while serious, do not necessarily require the same level of immediate, life-saving intervention that the symptoms of the 22-year-old male suggest.