Which tool creates, joins, or removes volumes in a design?

The Boundary Fill tool is designed to create and manipulate solid volumes in a 3D space by defining the boundaries of the adjacent volumes. It allows users to choose specific regions to fill with material, effectively generating new solid shapes from defined spaces. By utilizing the boundaries of existing geometric entities, the Boundary Fill tool enables users to join multiple volumes together or create new volumes within specified limits.

This functionality is crucial in 3D modeling environments where the management of solid bodies and shapes is essential, providing flexibility in constructing complex geometric forms. It serves as a foundational tool in design workflows, particularly for creating intricate parts in mechanical design or architectural modeling.

The other choices, while related to volume manipulation, do not specifically emphasize the creation, joining, or removal of volumes in the same way. This distinct purpose makes the Boundary Fill the most appropriate tool for the question posed.