Which of the following is an example of a superconductor?

The choice of a superconductor correctly leads to high-temperature superconductors, which exhibit zero electrical resistance when cooled below a certain temperature, often close to that of liquid nitrogen. Superconductors are materials that can carry current without energy loss, which is a remarkable property utilized in various advanced technologies.

High-temperature superconductors are particularly relevant because they operate at temperatures that are more achievable and practical for applications compared to traditional superconductors, which require more extreme cooling methods. This allows them to be used in creating powerful magnetic fields and conducting electricity with great efficiency.

Although MRI scanners do utilize superconducting magnets to produce strong magnetic fields necessary for imaging, they themselves do not qualify directly as superconductors. However, they often rely on superconducting materials to function effectively.

Other options, such as wires for electrical conduction or light bulbs, typically experience electrical resistance, which is the opposite of what makes a superconductor valuable. Thus, they do not meet the criteria to be categorized as superconductors.