Which of the following describes a pulley?

A pulley is defined as a wheel on an axle or shaft designed to support movement and change direction of force using a rope or cable. When multiple sheaves are used together, they form a compound pulley system, which can increase mechanical advantage. This allows for easier lifting of heavy loads by distributing weight across multiple points.

The other options do not accurately define a pulley. A belt with a groove refers more to a belt system used in machinery, not the essential characteristics of a pulley. A wheel with multiple belts also implies a different context, focusing more on systems that utilize belts rather than the basic unit of a pulley itself. A type of winch suggests a specific application or tool rather than the fundamental definition of what a pulley is, which is primarily concerned with the wheel and the rope mechanism.