The correct option is
A y-axis
The given point is (0,6).
Hence, its x-coordinate is 0 and y-coordinate is 6.
We know that, x-coordinate of a point is the perpendicular distance of the point from y−axis and y-coordinate is the perpendicular distance from the x−axis.
Hence, the given point is at 0 units distance from y−axis and 6 units distance from the x−axis.
Therefore, the point lies on y−axis.