Which statement best defines a conductor?

• A. A material that allows electricity to flow through it easily.
• B. A material in which electrons are not able to move easily.
• C. The rate at which work is done.
• D. The unit of electrical resistance.

Answer: (B)

A conductor is a material that allows electricity to flow through it easily. This happens because in many conductors, especially metals, there are electrons that are not bound to a single atom and can move freely. When a potential difference is applied, these free electrons drift and create an electric current. That ease of movement is what makes conductors good at carrying current—think of copper wires in circuits.

The other descriptions point to different ideas: a material in which electrons cannot move easily describes an insulator, not a conductor. The rate at which work is done is power, and the unit of electrical resistance is the ohm—both separate concepts from what defines a conductor.