Answer:
A
Step-by-step explanation:
Under a counterclockwise rotation about the origin of 90°
a point (x , y ) → (- y, x ) , thus
X(1, - 1 ) → X'(1, 1 )
Y(3, 4 ) → Y'(- 4, 3 )
Z(5, - 1 ) → Z'(1, 5 ) → A
