Which sequence of transformations will change figure PQRS to figure P′Q′R′S′?
Counterclockwise rotation about the origin by 180 degrees followed by reflection about the x-axis
Counterclockwise rotation about the origin by 180 degrees followed by reflection about the y-axis
Counterclockwise rotation about the origin by 270 degrees followed by reflection about the x-axis
Counterclockwise rotation about the origin by 270 degrees followed by reflection about the y-axis