Correct Answer: C

Rationale: Monitoring blood glucose levels closely before surgery is the priority for a client with diabetes mellitus. This allows for early detection of any abnormalities and helps prevent hypo- or hyperglycemia complications that can arise during the perioperative period. Option A is incorrect because insulin dosing should be individualized based on the client's current blood glucose levels and the surgical plan. Option B is incorrect as abruptly holding oral hypoglycemic agents can lead to uncontrolled blood glucose levels. Option D is incorrect as adequate fluid intake is important for the client's hydration status and overall well-being before surgery.

Correct Answer: A

Rationale: The correct intervention for a client with pheochromocytoma is to administer beta-blockers to control blood pressure. Pheochromocytoma is a catecholamine-secreting tumor that can cause severe hypertension. Beta-blockers are used to block the effects of catecholamines and help control blood pressure in these clients. Encouraging a high-sodium diet (Choice B) would not be appropriate as it can worsen hypertension. Monitoring for signs of hyperglycemia (Choice C) is not directly related to managing pheochromocytoma. Restricting fluid intake (Choice D) may lead to dehydration and is not a recommended intervention for this condition.

Correct Answer: C

Rationale: A magnesium level of 1.0 mg/dL can cause a depressed ST segment on the ECG. Magnesium deficiency commonly leads to ST segment depression on an electrocardiogram. Prominent U waves are associated with hypokalemia, prolonged PR interval is seen in conditions like first-degree heart block, and widened QRS complexes are typically related to conditions affecting the conduction system of the heart, such as bundle branch blocks.

Correct Answer: C

Rationale: The correct answer is C. Glycosylated hemoglobin (HbA1c) reflects average blood glucose levels over the past 3 months. This test is used to assess long-term blood sugar control in individuals with diabetes. Choice A is incorrect because fasting is not required for an HbA1c test. Choice B is judgmental and not supported by the information provided. Choice D is not the most accurate statement to make based on the HbA1c result; adjusting insulin would depend on a more comprehensive assessment of the client's overall diabetes management.

Correct Answer: B

Rationale: The correct answer is B: Propylthiouracil. Propylthiouracil is an antithyroid medication used to manage hyperthyroidism by inhibiting the synthesis of thyroid hormones. Levothyroxine (Choice A) is typically used to treat hypothyroidism, the opposite of hyperthyroidism. Lithium (Choice C) is not used to treat hyperthyroidism but is commonly used to manage bipolar disorder. Metoprolol (Choice D) is a beta-blocker that may be used to manage symptoms like tachycardia associated with hyperthyroidism, but it is not the primary treatment for the condition.