Correct Answer: D

Rationale: Leukocytosis is defined as an increase in the total white blood cell count. A normal WBC count typically ranges from 4,500 to 10,000/mm³. A WBC count of 25,000/mm³, as indicated in choice D, is significantly higher than the normal range and clearly indicates leukocytosis.

Correct Answer: B

Rationale: Body hair plays an active role in preventing infection by acting as a filter to block pathogens. It helps to prevent harmful substances from entering the body through the skin, providing a physical barrier against potential infections.

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: A

Rationale: The correct answer is A because there are contraindications for chest X-rays, such as pregnancy or concerns about radiation exposure. Patients may need to remove jewelry and metallic objects to prevent interference with the imaging. While a signed consent is typically not required for a routine chest X-ray, there are specific situations where consent may be necessary. It is essential for patients to follow fasting instructions before certain types of chest X-rays to obtain accurate results.

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.