Dual Nature Of Radiation

Graph shows the variation of de-Broglie wavelength \((\lambda)\) versus \(\frac{1}{\sqrt{V}}\) where '\(V\)' is the accelerating potential for four particles A, B, C, D carrying same charge but of masses \(\mathrm{m_1, m_2, m_3, m_4}\). Which on represents a particle of largest mass?