Which of the Following Is an Example of Implied Consent

Which of the following is an example of implied consent?

A) Patient signs a consent form for surgery after discussing the procedure with her physician.
B) Patient makes an appointment and arrives at imaging center for an X-ray.
C) Patient fills out advance directive documents with instructions if she becomes unable to make decisions.
D) Patient does not want treatment, but it is given because the physician believes the patient needs it.