Which of the following best describes a body belt's design and use?

A body belt is specifically designed for positioning or travel restraint in contexts such as ladder work. Its primary function is to help stabilize a worker while they are in a specific position, particularly when working at heights or in difficult positions. This design allows for safe and efficient movement and stability without compromising the user's safety, which is crucial when they're working in elevated areas or confined spaces.

The other options, while they mention belts or harnesses, do not accurately describe a body belt's intended purpose. For example, a full-body harness is specifically used for high-angle rescues and fall protection, ensuring a worker's entire body is secured. A support belt for heavy lifting focuses on back support for lifting tasks rather than positioning. A tool belt is primarily for carrying tools and does not serve a safety or restraint function. Thus, the focus on positioning and restraint in option B clearly aligns with the specific design and use of a body belt.