To determine that the dilated triangle \( A'B'C' \) is similar to triangle \( ABC \) using the AA criterion (Angle-Angle criterion), the best response from the options provided is:
Translate the dilated triangle so one of its angles exactly matches the corresponding angle in the original triangle; repeat using a different pair of angles.
This method allows you to establish the similarity by showing that two angles in triangle \( ABC \) are congruent to two angles in triangle \( A'B'C' \), which is sufficient to prove that the two triangles are similar based on the AA criterion. This criterion states that if two angles in one triangle are equal to two angles in another triangle, the triangles are similar.
The other options involve reflections, finding side lengths, or comparing ratios which do not directly apply the AA criterion for proving similarity through angle comparison.