Correct Answer: B

Rationale: In a child with a head injury, the development of diabetes insipidus can occur due to pituitary hypofunction, leading to a deficiency of antidiuretic hormone. An elevated sodium level (hypernatremia) is a key finding in diabetes insipidus due to the excessive loss of free water in the urine, resulting in increased sodium concentration in the blood.

Correct Answer: B

Rationale: Cimetidine binds to androgen receptors, producing receptor blockade, which can cause enlarged breast tissue, reduced libido, and impotence. All these effects reverse when dosing stops. Amoxicillin, metronidazole, and omeprazole are not associated with gynecomastia.

Correct Answer: C

Rationale: In Kawasaki disease, a child typically presents with a fever that is unresponsive to antipyretics because the disease is characterized by systemic inflammation. The persistent fever is a hallmark feature of the disease and can last for more than five days despite treatment with antipyretics.

Correct Answer: A

Rationale: Intussusception is a condition where one segment of the intestine telescopes into another, causing obstruction. The classic presentation includes currant jelly stools, which are a mixture of blood and mucus due to the sloughing of the intestinal mucosa. This finding is a result of the compromised blood supply to the affected area and is a key characteristic associated with intussusception.

Correct Answer: D

Rationale: The nurse should keep the infant’s elbow restrained to prevent injury to the surgical site.