To determine the mapping function for a 90° counterclockwise rotation about the origin, we can use the following transformation for a point \((x, y)\):
\[ (x, y) \rightarrow (-y, x) \]
This means that the new coordinates after the transformation will be \((-y, x)\).
If you have specific options listed, please provide them, and I can help you identify the correct option based on this transformation.