Answer:
(d) A'(5, -1)
Explanation:
You want the coordinates of A(1, 5) after it has been rotated 270° CCW about the origin.
Rotation
The transformation for rotation 270° CCW is the same as that for rotation 90° CW:
(x, y) ⇒ (y, -x)
For the given point, this is ...
A(1, 5) ⇒ A'(5, -1)
The image of A is A'(5, -1), choice D.