A photosensitive metallic surface has work function `hv_0`.If photons of energy `2 h v_0` fall on this surface,the electrons come out with a maximum velocity of `4 xx 10^6 m s^(-1) `.When the photon energy is increased to `5 h v_0`,then maximum velocity of photoelectron will be:

Options

A. `2xx 10^7 m s^(-1)`
B. `2 xx 10^6 m s^(-1)`
C. `8 xx 10^6 m s^(-1)`
D. `8 xx 10^5 m s^(-1)`.