The intensity of X-rays from a Coolidge tube is plotted against wavelength as shown in the figure. The minimum wavelength found is ${\mathrm{\lambda }}_{\mathrm{c}}$ and the wavelength of the ${\mathrm{K}}_{\mathrm{\alpha }}$ line is ${\mathrm{\lambda }}_{\mathrm{K}}$. As the accelerating voltage is increased

• A

  $\left({\mathrm{\lambda }}_{\mathrm{K}}-{\mathrm{\lambda }}_{\mathrm{C}}\right)\mathrm{increases}$

• B

  $\left({\mathrm{\lambda }}_{\mathrm{K}}-{\mathrm{\lambda }}_{\mathrm{C}}\right)\mathrm{decreases}$

• C

  ${\mathrm{\lambda }}_{\mathrm{K}}\mathrm{increases}$

• D

  ${\mathrm{\lambda }}_{\mathrm{K}}\mathrm{decreases}$