Given that ΔA′B′C′ is a dilation of ΔABC, how are the angles and side lengths of the preimage and image related?
A. The angles are congruent and the side lengths are congruent.
B. The angles are congruent and the side lengths are proportional.
C. The angles are proportional and the side lengths are congruent.
D. The angles are proportional, and the side lengths are proportional.