Final answer:
Enalapril can cause a persistent cough as an adverse effect.
Step-by-step explanation:
The nurse should instruct the client to monitor for persistent cough as an adverse effect of taking enalapril 20 mg P0 daily. Enalapril is an angiotensin-converting enzyme (ACE) inhibitor commonly used to treat hypertension and heart failure. A dry, persistent cough is a common side effect of ACE inhibitors and can be bothersome for some patients.