Final answer:
The statement that high-voltage transmission lines are wrapped in an insulating material is false; they are instead supported by insulators and kept at a safe distance to prevent the current from grounding.
Step-by-step explanation:
The statement that the high-voltage wires connected to tall metal-frame towers are held aloft by insulating connectors and are wrapped in an insulating material is false. In reality, these high-voltage wires are generally not covered with insulating material due to cost, weight, and maintenance considerations. Instead, they are kept at a safe distance from each other and from the ground, using insulators that are designed to support them while preventing electrical current from traveling down the tower structure.