What is the minimum height above the underlying designated play surface for roof lines on play structures?

Play structures, also known as playgrounds or jungle gyms, have specific height requirements to ensure the safety of children playing on them. According to the U.S. Consumer Product Safety Commission (CPSC), the minimum height above the designated play surface for roof lines on play structures is 84 inches. This is to prevent any potential head injuries and allow sufficient clearance for children to play under the roof line. Options A, C, and D are incorrect because they are either lower or higher than the recommended minimum height. It is important to follow these safety guidelines when constructing and using play structures to prevent any accidents or injuries.