Which constraint makes selected geometric entities mirror images about a selected line or axis?

The constraint that creates mirror images of selected geometric entities about a specified line or axis is known as the symmetry constraint. This tool is essential in parametric modeling, as it ensures that one side of a design is a mirrored reflection of the other, maintaining perfect geometric relationships and proportionality.

When using the symmetry constraint, users can select the entities they wish to mirror and the axis along which the mirroring occurs. This not only saves time during the design process but also enhances design accuracy, as any modifications made to one side automatically reflect on the other side.

The other options do not specifically refer to the functionality of mirroring shapes about an axis or line. For example, while the reflection is a term that might suggest a similiarity to mirroring, it doesn't define the specific behavior applied in parametric design software like Autodesk Inventor. Thus, the symmetry constraint is specifically aimed at ensuring entities are truly mirrored, emphasizing its role in maintaining balanced designs.