Final answer:
In an emergency preparedness plan, priority care should be provided to clients in the Immediate category, as these individuals require urgent attention to save their lives.
Step-by-step explanation:
In the context of an emergency preparedness plan, the nurse should provide priority care to clients who are in the Immediate category during a disaster. This category is established to prioritize individuals who require urgent medical attention to save their lives or prevent serious complications. On the other hand, the other categories of triage involve patients who can wait for treatment (Delayed), those with minor injuries (Minimal), and those who are not likely to survive (Expectant).