A convex lens of focal length f produces a real image $\frac{1}{\mathrm{n}}$ times than that of the size of the object. The distance of the object from the lens is 

• A

  nf

• B

  $\frac{\mathrm{f}}{\mathrm{n}}$

• C

  $(\mathrm{n}+1)\mathrm{f}$

• D

  $(\mathrm{n}-1)\mathrm{f}$