A peace officer who encounters an injured person while discharging their official duties _____ immediately request EMS, provide first aid to treatment to the extent of the officer's skills and training.

In this context, the correct term indicates a legal obligation. The term "shall" implies a mandatory action that a peace officer is required to undertake under specific circumstances. When a peace officer encounters an injured person while performing their official duties, "shall" denotes that the officer is legally compelled to take action by immediately requesting emergency medical services (EMS) and providing first aid to the extent of their training and abilities.

This is important as it emphasizes the duty and responsibility of peace officers to protect life and ensure the well-being of individuals, particularly those who are injured. The use of this term ensures there is no ambiguity regarding the officer's obligation to act, reinforcing the legal expectation that officers will intervene in emergencies.

In contrast, terms like "must," "should," or "may" do not carry the same legal weight. "Must" can convey a strong necessity similar to "shall," but is less commonly used in legal texts. "Should" suggests a recommendation without a binding obligation, and "may" indicates permission without suggesting any requirement to act. Hence, the use of "shall" clearly delineates the officer’s responsibilities in such situations, establishing a concrete legal standard for their conduct.