Which Intervention by a Psychiatric Nurse Best Applies the Ethical

Which intervention by a psychiatric nurse best applies the ethical principle of autonomy? The nurse:

A) explores alternative solutions with a patient,who than makes a choice.
B) suggests that two patients who were fighting be restricted to the unit.
C) intervenes when a self-mutilating patient attempts to harm self.
D) stays with a patient demonstrating a high level of anxiety.