Select the correct answer. ΔABC underwent a sequence of rigid transformations to give ΔA′B′C′. Which transformations might have taken place?

A.
a reflection across the y-axis followed by a reflection across the x-axis

B.
a rotation 90° clockwise about the origin followed by a reflection across the x-axis

C.
a rotation 270° clockwise about the origin followed by a reflection across the x-axis

D.
a reflection across the x-axis followed by a reflection across the y-axis