Final answer:
The nurse's priority teaching for a client with heart failure prescribed enalapril is to avoid using salt substitutes.
Step-by-step explanation:
The nurse's priority teaching for a client with heart failure who is prescribed enalapril (Vasotec) would be:
a. "Avoid using salt substitutes." Salt substitutes contain potassium, and enalapril can cause potassium levels to rise. Therefore, it is important for the client to avoid using salt substitutes to prevent hyperkalemia, which can be dangerous for individuals with heart failure.