Final answer:
The most appropriate nursing action is to assist the client in expressing feelings.
Step-by-step explanation:
The most appropriate nursing action when a client with viral hepatitis states, 'I am so yellow,' is to assist the client in expressing feelings. Jaundice, a common symptom of hepatitis, causes yellowing of the skin, mucous membranes, and sclera of the eyes. By assisting the client in expressing their feelings, the nurse can provide emotional support and create a therapeutic environment.