The potential energy of a particle of mass $m$ is given by,$U(x) = \begin{cases} E_0 & 0 \leqslant x \leqslant 1 \\ 0 & x > 1 \end{cases}$. $\lambda_1$ and $\lambda_2$ are the de-Broglie wavelengths of the particle when $0 \leqslant x \leqslant 1$ and $x > 1$ respectively. If the total energy of the particle is $2 E_0$,the ratio $\frac{\lambda_1}{\lambda_2}$ will be

• A
  $1$
• B
  $2$
• C
  $\sqrt{2}$
• D
  $\frac{1}{\sqrt{2}}$