What are the runways on which the crane runs up and down the plant called?

The correct answer is rails. In the context of overhead cranes, rails refer specifically to the steel tracks installed along which the crane travels. These rails are designed to support the weight of the crane and provide a smooth surface for movement, ensuring that the crane can operate safely and efficiently throughout the facility.

Tracks and beams might refer to similar components in different contexts, but they do not specifically denote the structure that supports the crane's movement like rails do. Paths typically refer to wider concepts that suggest a direction or route rather than the physical infrastructure required for crane operation. In summary, rails are the specific components that facilitate the vertical and horizontal movement of the overhead crane within a facility, providing both support and guidance during operation.