Correct Answer: A

Rationale: The symptoms of fatigue, muscle cramping, and muscle weakness in a patient after starting furosemide therapy are indicative of hypokalemia. Furosemide is a loop diuretic that can lead to potassium depletion, causing hypokalemia. Hypokalemia can manifest with muscle weakness, cramps, and fatigue due to alterations in neuromuscular function and decreased ATP production.

Correct Answer: D

Rationale: Chest physiotherapy is the most effective intervention in cases of impaired gas exchange related to increased secretions. This technique helps mobilize and clear secretions from the airways, thereby improving gas exchange in the lungs. Placing a humidifier or administering oxygen by high humidity face mask may provide moisture but may not directly address the clearance of secretions. Encouraging increased fluid intake can help with hydration but may not address the underlying issue of impaired gas exchange due to secretions.

Correct Answer: A

Rationale: Obtaining a sputum specimen early in the morning is the most appropriate time because secretions have accumulated overnight. This timing provides the best sample with the least contamination, leading to more accurate culture results and aiding in diagnosing respiratory infections effectively.

Correct Answer: D

Rationale: The appropriate needle size for insulin injection is 25G, 5/8" long. This size allows for accurate and comfortable insulin administration in subcutaneous tissue.

Correct Answer: C

Rationale: Accompanying the patient for his walk is the appropriate nursing intervention in this scenario to ensure his safety during his first ambulation. This allows the nurse to provide immediate assistance if needed and ensures the patient's well-being during this critical postoperative period.