Photons of energy $7 \mathrm{eV}$ are incident on two metals A and B with work functions $6 \mathrm{eV}$ and $3 \mathrm{eV}$ respectively. The minimum de Broglie wavelengths of the emitted photoelectrons with maximum energies are $\lambda_{\mathrm{A}}$ and $\lambda_{\mathrm{B}}$, respectively where $\lambda_{\mathrm{A}} / \lambda_{\mathrm{B}}$ is nearly

• A

  $0.5$
• B

  $1.4$
• C

  $4.0$
• Correct answer
  D

  $2.0$

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