What is a sliding bevel used for?

A sliding bevel is a tool specifically designed to transfer angles and mark them onto other surfaces. It features a movable arm that can be adjusted to any angle, allowing a user to replicate this angle on materials such as wood or metal. This makes it invaluable for tasks that require precise angular measurements, such as carpentry or metalworking, where accurate angle marking is essential.

The other choices represent functions served by different tools. Internal dimension measuring typically involves calipers or similar devices, while establishing right angles is the primary function of a square. Cutting keyholes would typically be accomplished with specialized tools like keyhole saws or drills, rather than a sliding bevel. Thus, the versatility of the sliding bevel to mark any angle is what makes option B the correct answer.