What type of knot is the best choice to prevent the end of a rope from running out of a tackle or pulley?

The figure eight knot is an excellent choice for preventing the end of a rope from slipping out of a tackle or pulley due to its design and structure. This knot forms a robust, secure loop that keeps the end of the rope from unraveling. Its shape provides a considerable amount of friction, helping to keep the knot secure under load.

Additionally, the figure eight knot is relatively easy to tie and untie, making it practical for rigging applications where adjustments are often necessary. It also retains much of the rope's strength compared to other knots, which is crucial in industrial rigging where safety and efficiency are paramount.

Other knot types serve different purposes. The bowline knot creates a fixed loop at the end of a rope but may not hold as securely when there's movement or tension changes involved. The square knot, while effective for joining two ropes, is not ideal for stopping a rope's end from slipping through a pulley. The granite knot, although used in some contexts, is less common in rigging tasks compared to the figure eight knot, especially for the purpose described in this scenario.