In Young's double slit experiment, the fringe width is $1\times {10}^{-4} \mathrm{m}$ if the distance between the slit and screen is doubled and the distance between the two slits is reduced to half and wavelength is changed from $6.4\times {10}^{-7} \mathrm{m}$ to $4.0\times {10}^{-7} \mathrm{m}$, the value of new fringe width will be

• A

  $0.15\times {10}^{-4}\mathrm{m}$

• B

  $2.0\times {10}^{-4}\mathrm{m}$

• C

  $1.25\times {10}^{-4}\mathrm{m}$

• D

  $2.5\times {10}^{-4}\mathrm{m}$