Common end fittings for blocks include which of the following?

The correct answer highlights that hooks are indeed common end fittings for blocks used in rigging and lifting applications. Hooks are essential components that facilitate the attachment of the load to the block. They provide a secure connection for various lifting equipment, ensuring that loads can be safely hoisted and manipulated.

In rigging, blocks are often employed to change the direction of the force applied or to gain a mechanical advantage in lifting heavy objects. The function of hooks at the end of these blocks is crucial, as they allow for quick and safe engagement and disengagement of the load, enabling efficient operations.

Other options include items such as pulleys, shells, and standing blocks, which serve different functions in the context of lifting equipment. While pulleys are integral parts of a block system and facilitate the movement of rope or cable, they are not considered end fittings. Shells may refer to the outer casing of a block, and standing blocks are fixed, meaning they do not move or lift a load in the way that hooks do. However, hooks have a direct and essential role in the connection to loads, solidifying their place as common end fittings in various rigging systems.