Which sequence of transformations will map triangle ABC onto its congruent imago. triangle A'B'C'?
A. a 180° clockwise rotation about the origin, followed by a translation two units down
B. a reflection across the y-axis, followed by a translation two units down
C. a reflection across the x-axis, followed by a reflection across the y-axis
D. a translation seven units to the left, followed by a translation five units dow