Correct Answer: C

Rationale: The correct answer is C: RSV, influenza, and adenovirus. The CDC recommends respiratory hygiene and etiquette to prevent the transmission of respiratory syncytial virus (RSV), influenza, adenovirus, and other droplet-transmitted unknown viruses. Choices A, B, and D are incorrect because HBV, Hib, pertussis, HSV, and varicella are not typically transmitted via droplets but through other modes of transmission.

Correct Answer: B

Rationale: Weighing diapers is the most accurate way to estimate urine output in a child who is not toilet trained. This method provides a measurable and reliable estimate of fluid output.

Correct Answer: C

Rationale: A high reticulocyte count indicates that the bone marrow is producing more red blood cells, which is a sign of recovery from anemia as the body replenishes its iron stores and increases hemoglobin levels. Low hemoglobin (Choice A) would indicate ongoing anemia rather than improvement. A normal platelet count (Choice B) and low hematocrit (Choice D) are not specific indicators of improvement in iron deficiency anemia.

Correct Answer: A

Rationale: In the case of severe isotonic dehydration, the initial fluid of choice is 0.9% normal saline. This solution is preferred because it helps to restore both fluids and electrolytes effectively. Options B, C, and D are not suitable for the initial management of severe isotonic dehydration. D5 0.2% (1/4) normal saline (Choice B) is a hypotonic solution and might worsen the imbalance. D5W (Choice C) is a hypotonic solution that does not contain electrolytes essential for rehydration. Albumin (Choice D) is a colloid solution used for specific indications like hypoproteinemia or hypoalbuminemia, not for initial rehydration in severe dehydration.

Correct Answer: A

Rationale: Fever increases metabolic rate, leading to insensible water loss, thus requiring increased fluid intake. Mechanical ventilation, CHF, and increased intracranial pressure generally require fluid restriction rather than increased fluid intake.