Which of these properties is preserved exclusively under dilation?

A. Symmetry

B. Similarity

3. Congruence

The property that is preserved under dilation is the similarity. The answer is letter A. Dilation of a figure starts from the very center of it and then continually increased or decreased depending on the desired size. It is similarity that is under dilation because no matter how big or small the size of the figure is, it has a similar feature from the original one.