Final answer:
High-voltage wires on tall towers are not wrapped in insulating material; air acts as the insulator, making the statement false.
Step-by-step explanation:
The statement that high-voltage wires are wrapped in an insulating material is false. High-voltage wires that you see on tall metal-frame towers are indeed held aloft by insulating connectors to prevent the electricity from grounding through the towers. However, these high-voltage wires are not wrapped in insulation. The air surrounding the wires serves as the insulator. This is possible because the air provides enough resistance to prevent significant current from flowing to other objects, as long as there is sufficient distance to other conductive materials.