Metals are lustrous in nature, having shiny appearance. Arrange the reasons given below in a sequence.
(a) Emission of radiation or light energy by excited electrons makes a metal shiny in appearance.
(b) The electrostatic forces of attraction between metal ions and the mobile electrons is called metallic bond.
(c) The positive metal ions are surrounded by pool of electrons.
(d) When light falls on the crystal, electrons get excited.