In geometric transformations, what does congruence refer to?

Congruence in geometric transformations refers specifically to shapes that are identical in both shape and size. When two shapes are congruent, they can be transformed into one another through various means such as translations, rotations, or reflections without altering their size or proportions. This means that all corresponding sides and angles in the two shapes are equal, indicating that they maintain the same geometric properties despite possibly being located in different positions in space.

This understanding is fundamental in geometry, as congruence is often used to determine whether two figures are the same in terms of their fundamental characteristics. The other options provided do not correctly define congruence; for instance, having the same area does not necessarily mean the shapes are congruent, and shapes that vary in dimensions or do not overlap do not meet the criteria of congruence at all.