Correct Answer: B

Rationale: The correct dietary instruction for a child with GERD is to avoid gluten. Gluten is a protein found in wheat, barley, and rye, and it can exacerbate GERD symptoms in some individuals. Avoiding gluten can help reduce inflammation and irritation in the gastrointestinal tract, thereby alleviating symptoms of GERD. Choices A, C, and D are incorrect because while spicy foods, high-fat foods, and dairy products can trigger GERD symptoms in some individuals, avoiding gluten specifically is more relevant for managing GERD.

Correct Answer: C

Rationale: The correct answer is C: palpable olive-like mass. In pyloric stenosis, a palpable olive-like mass can often be felt in the abdomen due to the hypertrophied pyloric muscle. This mass is a key characteristic finding in infants with pyloric stenosis. Choice A, abdominal rigidity, is more commonly associated with conditions like peritonitis. Choice B, substernal retraction, is not typically seen in pyloric stenosis but can be a sign of respiratory distress. Choice D, marked distention of the lower abdomen, is not specific to pyloric stenosis and can be present in various abdominal conditions.

Correct Answer: C

Rationale: Infants with Down syndrome are at increased risk of congenital heart defects. Therefore, assessing for abnormal heart sounds is crucial during the physical examination. Bulging fontanels are not typically associated with Down syndrome and may indicate increased intracranial pressure. Stiff lower extremities are not a common finding in Down syndrome and may suggest other musculoskeletal issues. Unusual pupillary reactions are not typically linked to Down syndrome and may be indicative of neurological problems instead.

Correct Answer: D

Rationale: The correct answer is D: Severe coughing spells. Pertussis, also known as whooping cough, typically presents with severe coughing spells that can be followed by a characteristic 'whoop' sound. These coughing fits can be intense and prolonged, often causing the child to gasp for air between coughs. Option A, dry hacking cough, is a common symptom of other respiratory conditions like bronchitis. Option B, inspiratory stridor, is more commonly associated with conditions like croup. Option C, nasal congestion, is not a typical symptom of pertussis.

Correct Answer: D

Rationale: After undergoing surgery for pectus excavatum correction with steel bar placement, the nurse should instruct the parents to avoid placing the child in a side-lying position. This position should be avoided to prevent displacement of the steel bar, which could compromise the surgical outcome. Semi-Fowler, supine, and high Fowler positions do not pose the same risk of displacing the steel bar and are generally safe and comfortable for the child in this postoperative period.