Final answer:
High-voltage wires are not wrapped in an insulating material but are suspended in the air, which acts as a natural insulator. Insulating connectors are used to attach the wires to towers.
Step-by-step explanation:
The statement that high-voltage wires are wrapped in an insulating material is false. Typically, the high-voltage wires you see suspended from metal-frame towers are not individually wrapped in an insulating material.
Instead, they are designed to be sufficiently high above the ground and separated from each other by air gaps, which acts as a natural insulator. Insulating connectors are indeed used to connect the wires to the towers, preventing the electrical current from grounding through the tower structure.