Correct Answer: A

Rationale: The correct answer is 'A: Somnolence.' Somnolence can indicate lactic acidosis, which is manifested by extreme drowsiness, hyperventilation, and muscle pain. It is a rare but very serious adverse effect caused by metformin and should be reported to the provider promptly to prevent further complications.

Correct Answer: D

Rationale: Clozapine carries a risk for fatal agranulocytosis. To monitor for this serious adverse effect, it is crucial to check the client's white blood cell count weekly while they are on clozapine therapy.

Correct Answer: C

Rationale: Atenolol, a beta-blocker, can lead to bradycardia as an adverse effect due to its mechanism of action. The nurse should advise the client to monitor their pulse regularly, as a significant decrease may indicate bradycardia, a condition characterized by a slow heart rate.

Correct Answer: A

Rationale: The correct instruction for a client prescribed Lisinopril is to avoid salt substitutes. Lisinopril, an ACE inhibitor, can lead to hyperkalemia, hence the importance of avoiding salt substitutes that may contain potassium. Instructing the client to avoid salt substitutes helps prevent potential adverse effects of increased potassium levels.

Correct Answer: A

Rationale: The correct answer is to take simvastatin in the evening. This timing is recommended because nighttime is when the most cholesterol is synthesized in the body. By taking statin medications in the evening, it can enhance their effectiveness in reducing cholesterol levels.