What does a block hook consist of?

A block hook consists of an assembly of one or more sheaves within a frame, along with a hoist hook. The sheaves are designed to guide and support the ropes or cables used in lifting operations, allowing for the efficient management of the load being lifted. This arrangement not only facilitates the movement of heavy objects but also provides a mechanical advantage that can make lifting easier and more effective. The hoist hook is essential for securing the load to the block for safe lifting.

Other choices do not provide a complete or accurate description of a block hook. An assembly of ropes and pulleys primarily focuses on the lifting mechanism without specifically mentioning sheaves and the hook assembly. A single sheave attached to a crane would not encompass a block hook's complexity, as it lacks the necessary components for load management. Similarly, a type of safety latch, while important for securing hooks, does not capture the fundamental construction and function of a block hook.