Monochromatic light of wavelength λ = 4770 ˚A is incident separately on the surfaces of four different metals A, B, C and D. The work functions of A, B, C, and D are 4.2 eV, 3.7 eV,3.2 eV and 2.3 eV, respectively. The metal/ metals from which electrons will be emitted is/are: