After absorbing a slowly moving neutron of mass ${\mathrm{m}}_{\mathrm{N}}$ (momentum $~0$); a nucleus of mass $\mathrm{M}$ breaks into two nuclei of masses ${\mathrm{m}}_1$ and $5{\mathrm{m}}_1$ ($6{\mathrm{m}}_1=\mathrm{ }\mathrm{M}\mathrm{ }+\mathrm{ }{\mathrm{m}}_{\mathrm{N}}$), respectively. If the de-Broglie wavelength of the nucleus with mass ${\mathrm{m}}_1$ is $\mathrm{\lambda }$, then de- Broglie wavelength of the other nucleus will be

• A

  $25\mathrm{\lambda }$
• B

  $5\mathrm{\lambda }$
• C

  $\frac{\mathrm{\lambda }}{5}$
• Correct answer
  D

  $\mathrm{\lambda }$

Hence, the correct answer is option: 'D'.