Which insulator type is often used in conjunction with overhead power lines to support the wires?

The correct answer encompasses all the mentioned types of insulators—porcelain, polymer, and glass—because each of these materials is commonly utilized in overhead power lines for insulation and support.

Porcelain suspension insulators are made from ceramic materials that can withstand high voltages and harsh environmental conditions. They are known for their durability and resistance to moisture, making them ideal for long-term outdoor use in power distribution systems.

Polymer suspension insulators, on the other hand, use a composite material that combines lightweight advantages with high electrical performance. They are particularly valued for their resistance to pollution and their ability to remain functional even in severe weather conditions. The lighter weight of polymer insulators also aids in reducing the load on towers.

Glass suspension insulators have been used historically and are recognized for their high resistance to electrical conductivity and environmental stresses. They provide excellent visibility to ensure maintenance checks and are often more resilient to physical damage compared to others.

Thus, the variety of insulator types each contribute unique benefits that are suitable for different conditions and requirements in overhead power line systems, leading to the conclusion that all listed options are valid choices for insulators supporting electrical wires.