Final answer:
The line of reflection that maps point K to point A is y = x.
Step-by-step explanation:
To determine the line of reflection that maps point K to point A, we need to find the mirror image of point K with respect to a line or axis. The mirror image will have the same distance from the line of reflection as the original point, but on the opposite side.
In this case, we can observe that the line y = x reflects points horizontally and vertically. Therefore, the mirror image of point K(10,3) would be (-3,-10) on the line y = x. So, the correct answer is a) ( y = x ).