Final answer:
The most beneficial intervention for parents worried about their son's ostomy care due to Hirschsprung disease is to arrange a meeting with a wound, ostomy, and continence nurse for personalized education and support.
Step-by-step explanation:
The most helpful intervention for parents of a boy with Hirschsprung disease who are anxious about caring for his ostomy post-surgery would be D) Having a wound, ostomy, and continence nurse meet with them. This specialist can provide the parents with personalized education and support on the care and management of the ostomy. They would address concerns such as changing the bag, skin care, and monitoring for possible complications. This hands-on guidance can be critical for easing parental anxiety and ensuring high-quality care for their son during the postoperative period.