A translation to the right has been applied to triangle ABC such that side AB coincides with side DE and side BC coincides with side EF, thus demonstrating that angle B and angle E have the same measure. What is true about side AC? A. Side AC coincides with side DF, because both are sides of equilateral triangles. B. Side AC coincides with side DF, because the respective endpoints of both segments coincide. C. It cannot be determined that side AC coincides with side DF, because no other relationships between corresponding angles are known. D. It cannot be determined that side AC coincides with side DF, because it is not known how many units to the right triangle ABC has been translated.