Triangle RST was transformed using the rule (x, y) → (–x, –y). The vertices of the triangles are shown.R (1, 1)S (3, 1)T (1, 6) R' (–1, –1)S' (–3, –1)T' (–1, –6)
A
The transformation was a 90° rotation about the origin.B
The transformation was a 180° rotation about the origin.C
The transformation was a 270° rotation about the origin.D
The transformation was a 360° rotation about the origin.