A proton and an $\alpha$ particle are accelerated , using the same potential difference . How are the de- Broglie wave length $\lambda_p$ and $\lambda_{\alpha}$ related to each other ?

Question

$\begin{array}{1 1} 2 \sqrt 2 \\ \sqrt 2\\ 3 \sqrt 2 \\ 4 \sqrt 2 \end{array}$