Final answer:
The Nurse Practice Act or equivalent is the best source to address a nurse's concern about whether an assigned duty falls within the scope of their practice.
Step-by-step explanation:
The nurse's concern about an assigned duty falling outside the scope of nursing practice can best be addressed by consulting the Nurse Practice Act or similar regulatory framework that defines the scope of nursing practice for the state or region in which the nurse is practicing. This document is a legal outline of what nurses can and cannot do in their professional capacity and should be the first reference to determine whether a task is appropriate. It is important to note that the scope of practice can also be influenced by the policies of the employing healthcare institution and the nurse's own qualifications and certifications.