A plane mirror is placed at the bottom of the tank containing a liquid of refractive index `mu`. P is a small object at a height h above the mirror. An observer O vertically above P, outside the liquid sees P and its image in the mirror. The apparent distance between these two will be
A. `2muh`
B. `(2h)/(mu)`
C. `(2h)/(mu-1)`
D. `h(1+1/(mu))`