When a figure is rotated 90 degrees counterclockwise about the origin, the point \((x, y)\) transforms according to the following mapping:
\[ (x, y) \rightarrow (-y, x) \]
This means that the x-coordinate is replaced by the negative of the y-coordinate, and the y-coordinate is replaced by the x-coordinate.
Therefore, the correct option is:
Option #1: (x, y) → (-y, x)