The correct option is A 12.5 cm in front of mirror m1.
For first reflection at mirror m1,
This first image will act as the object for the plane mirror m2.
For second reflection at plane mirror m2,
So, v=+10 cm
This second image will act as the virtual object for the mirror m1.
For third reflection at mirror m1,
Thus, the final image is formed at 12.5 cm in front of mirror m1.