A nurse is assisting with planning care for a school-age child who has suspected pertussis. Which of the following interventions is the nurse's priority to include?

A. Offering small amounts of oral fluids frequently: Providing fluids helps prevent dehydration from coughing and fever, but it is not the top priority when preventing disease transmission to others is urgent. B. Obtaining a nasopharyngeal culture: This is essential for confirming the diagnosis of pertussis, but it is not the first action to protect others or reduce immediate risk of spread. C. Implementing droplet precautions: Pertussis spreads via respiratory droplets, so placing the child on droplet precautions is the priority to prevent transmission to others, especially vulnerable infants and unvaccinated individuals. D. Encouraging family members' compliance with antibiotic therapy: This is important in reducing the spread of pertussis and treating close contacts, but it follows after immediate infection control measures are implemented.