Final answer:
The statement is false; high-voltage wires are not wrapped in insulating material but are insulated by the surrounding air and supported by insulating connectors.
Step-by-step explanation:
The statement that high-voltage wires are wrapped in insulating material is false. High-voltage wires, such as those seen connected to tall metal-frame towers, are actually not wrapped in any insulating material. They are held aloft by insulating connectors to prevent the electricity from grounding through the towers. However, the wires themselves are bare and are insulated by the air around them, which acts as the insulating material. This setup is efficient because at high altitudes where these wires are located, the air is less conductive and thus it helps to prevent electricity from arcing.