What type of expressions can be deleted using the Expression dialog box?

The correct choice indicates that the Expression dialog box is specifically designed to manage expressions that are currently not in use within a model or design. This means you can identify and remove expressions that do not contribute to any features or calculations in your design.

When dealing with expressions, it's common to create many that may later become irrelevant as the design evolves. The ability to delete these unused expressions helps maintain a clean and organized workspace, reducing clutter and ensuring that only relevant parameters are retained.

On the other hand, all defined expressions, locked expressions, and referenced expressions serve specific roles within the design and cannot be deleted through this dialog box. Defined expressions are generally tied to certain features or parameters, locked expressions are protected from being altered or deleted due to user settings, and referenced expressions are actively contributing to calculations or relationships within the model. This delineation is important to ensure the integrity and functionality of the design attributes. Thus, focusing on deleting only the expressions that no longer serve a purpose is crucial for effective design management.