Which statement best describes an insulator?

• A. Insulators convert electrical energy into light.
• B. Insulators are always metal.
• C. Insulators resist current flow.
• D. Insulators conduct electricity readily.

Answer: (C)

Insulators resist current flow, meaning they have high resistance and limit how easily electrons can move through them. This property keeps electricity contained and prevents shocks or short circuits. Materials like rubber, plastic, and glass are common insulators because their electrons aren’t free to move when voltage is applied. They’re used to coat wires and separate components so current stays on its intended path. The idea that insulators convert electrical energy into light isn’t correct—that’s what devices like bulbs do. It’s also not true that insulators are always metal or that they conduct electricity readily; metals are typically conductors, and insulators are those that do not conduct well.