Correct Answer: D

Rationale: The correct laboratory test to monitor the therapeutic effect of warfarin is the PT/INR. Warfarin affects blood clotting, and the PT/INR levels indicate the effectiveness of the medication in preventing clot formation. Therefore, monitoring PT/INR levels helps ensure that the client is within the therapeutic range and is protected from potential complications related to clotting.

Correct Answer: C

Rationale: Iron supplements commonly cause constipation as a side effect. Increasing fiber intake can help alleviate this issue by promoting regular bowel movements and preventing constipation.

Correct Answer: A

Rationale: Warfarin is classified as an anticoagulant, which means its primary function is to prevent the formation of blood clots. By inhibiting the synthesis of certain clotting factors in the liver, warfarin reduces the blood's ability to clot, making it an important medication in preventing conditions like strokes and deep vein thrombosis.

Correct Answer: A

Rationale: Metoprolol, a beta-blocker, is contraindicated in clients with bradycardia as it can further lower the heart rate, potentially leading to more serious complications. Bradycardia is defined as a heart rate below 60 beats per minute and administering metoprolol in such cases can exacerbate this condition, causing adverse effects on cardiac output.

Correct Answer: B

Rationale: Lithium is classified as a mood stabilizer due to its primary use in managing bipolar disorder, where it helps stabilize mood swings and prevent episodes of mania and depression. While it can have other effects on the body, its main therapeutic role lies in its mood-stabilizing properties.