A client has been prescribed an anticoagulant medication by the health care provider. The nurse has ensured that the client understands the medication's use, rationale, side effects, benefits, and risks of taking and not taking the medication. By documenting the client's refusal of the medication and returning the medication to the pharmacy, which ethical principle is the nurse demonstrating?
a. Autonomy
b. Fidelity
c. Beneficence
d. Justice