Which statement best explains whether △pqr is congruent to △xyz? a. △pqr is congruent to △xyz because △pqr can be mapped to △xyz by a rotation of 180° about the origin. b.△pqr is congruent to △xyz because △pqr can be mapped to △xyz by a reflection across the y-axis followed by a reflection across the x-axis. c.△pqr is congruent to △xyz because △pqr can be mapped to △xyz by a translation 5 units down followed by a reflection across the y-axis. d.△pqr is not congruent to △xyz because there is no sequence of rigid motions that maps △pqr to △xyz.