Final answer:
Transformations can be rigid (isometric) or nonrigid. Rigid transformations preserve size and angles, whereas nonrigid transformations do not. The question's context suggests a rigid transformation if size and angle congruency are maintained.
Step-by-step explanation:
When discussing transformations in mathematics, there are several key terms that help describe the nature of the transformation. A rigid transformation is one where the size and shape of the figure are preserved; this includes transformations like rotations and reflections. Alternatively, a nonrigid transformation, also known as a deformation, does change the size and/or shape of the figure; examples of this include dilations or warping effects. An isometric transformation is another term for a rigid transformation.
If the transformation is described as one where the size is preserved, it suggests that the figure remains congruent to its original, which is a property of a rigid or isometric transformation. If the angles are not preserved, this would imply a nonrigid transformation, as rigid transformations maintain angle congruency.