A 10-month-old patient presents to the nurse practitioner for treatment of mild bronchiolitis. Initial treatment should include:

Rationale: A. Inhaled bronchodilators have limited efficacy in mild bronchiolitis and are not routinely recommended for initial treatment. B. Over-the-counter antihistamines are not effective for bronchiolitis in infants. C. Cough suppressants are not recommended in infants due to potential side effects and lack of proven benefit. D. Supportive care is the mainstay of treatment for mild bronchiolitis, including ensuring adequate hydration, monitoring oxygenation, and providing comfort measures. Most cases are self-limited and resolve without pharmacologic intervention.