Final answer:
High-voltage power lines are typically bare and not insulated; the air around them acts as the insulator. Insulation for such lines would be impractical due to its weight and expenses.
Step-by-step explanation:
The statement that high-voltage wires, which are connected to tall metal-frame towers and held aloft by insulating connectors, are wrapped in an insulating material is false. High-voltage power lines are typically bare and not insulated because the air around them acts as an insulator. Insulation is not practical or necessary for such high-voltage lines since it would require a thick, unwieldy coating, which would be incredibly heavy, difficult to handle, and expensive. Moreover, the height and isolation of power lines prevent accidental contact with people and objects, thus insulation at the point of transmission is not needed. It is at the end-user access points, such as within a home or business where lower voltage wiring must be insulated for safety.