Final answer:
The claim that high-voltage wires are wrapped in insulating material is false. They are held by insulating connectors but are not individually insulated due to practicality and cost.
Step-by-step explanation:
The statement that high-voltage wires are wrapped in an insulating material is false. The high-voltage wires that you see atop tall metal towers are indeed held aloft by insulating connectors. However, these connectors are what prevent the live, high-voltage wires from coming into contact with the towers and grounding. The wires themselves are not insulated because they are high above the ground, where the probability of unintended contact with people or objects is very low, which makes wrapping them in insulation unnecessary. Additionally, at high voltages, the thick insulation necessary would be impractical and expensive.