An object is gradually moving away from the focal point of a concave mirror along the axis of the mirror. The graphical representation of the magnitude of linear magnification (m) versus distance of the object from the mirror (x) is correctly given by (Graphs are drawn schematically and are not to scale)

For the magnitude of linear magnification of a concave mirror:  $$m = \left|\frac{f}{f-u}\right| = \left|\frac{f}{f-x}\right|$$

For an object moving away from the focal point ($$x > f$$):  $$m = \frac{f}{x-f}$$

Analyzing the boundary points for the graph:

As $$x \to f^{+}$$, $$m \to \infty$$ (asymptotic line at $$x=f$$).

At $$x = 2f$$ (center of curvature), $$m = \frac{f}{2f-f} = 1$$.

As $$x \to \infty$$, $$m \to 0$$.